Base station apparatus, terminal apparatus, communication method, and integrated circuit

ABSTRACT

A terminal apparatus includes: a reception unit configured to receive an MIB that configures a first CORESET, receive an SIB1 that configures a second CORESET, receive first information that configures an initial UL BWP and second information that configures an additional UL BWP, and receive a first DCI format that schedules a PUSCH in a common search space; and a transmission unit configured to specify a set of allocated resource blocks based on a first field included in a first DCI format and transmit a PUSCH in an active UL BWP, the active UL BWP being either the initial UL BWP or the additional UL BWP, the first value indicated by a first field is provided based on the size of the initial UL BWP, a first start position that is a start position of a set of allocated resource blocks, and the number of first resource blocks continuously allocated, and the common search space is used for a random access procedure.

TECHNICAL FIELD

The present invention relates to a base station apparatus, a terminalapparatus, a communication method, and an integrated circuit. Thisapplication claims priority based on Japanese Patent Application No.2018-134079 filed on Jul. 17, 2018, the contents of which areincorporated herein by reference.

BACKGROUND ART

Technical studies and standardization of Long Term Evolution(LTE)-Advanced Pro and New Radio (NR) technology, as a radio accessscheme and a radio network technology for fifth generation cellularsystems, are currently conducted by the Third Generation PartnershipProject (3GPP) (NPL 1).

Fifth generation cellular systems require three anticipated scenariosfor services, that is, enhanced Mobile BroadBand (eMBB) which realizeshigh-speed and high-capacity transmission, Ultra-Reliable and LowLatency Communication (URLLC) which realizes low-latency andhigh-reliability communication, and massive Machine Type Communication(mMTC) that allows a large number of machine type devices to beconnected, such as in Internet of Things (IoT).

CITATION LIST Non Patent Literature

NPL 1: RP-161214, NTT DOCOMO, “Revision of SI: Study on New Radio AccessTechnology”, June 2016

SUMMARY OF INVENTION Technical Problem

An object of an aspect of the present invention is to provide a terminalapparatus, a base station apparatus, a communication method, and anintegrated circuit that enable efficient communication in a wirelesscommunication system as described above.

Solution to Problem

(1) To accomplish the object described above, aspects of the presentinvention are contrived to provide the following measures. In otherwords, a terminal apparatus according to an aspect of the presentinvention includes: a reception unit configured to receive an MIB thatconfigures a first control resource set (CORESET), receive an SIB1 thatconfigures a second CORESET, receive first information that configuresan initial uplink bandwidth part (UL BWP) and second information thatconfigures an additional UL BWP, and receive a first DCI format thatschedules a PUSCH in a common search space; and a transmission unitconfigured to identify a set of allocated resource blocks based on afirst field included in the first DCI format and transmit the PUSCH inan active UL BWP, the active UL BWP being a UL BWP resulting fromactivation of either the initial UL BWP or the additional UL BWP,wherein in a case that the common search space is a first common searchspace, a first value indicated by the first field is provided based on asize of the initial UL BWP, a first start position, and the number offirst resource blocks continuously allocated, the first common searchspace is a common search space used for a random access procedure, aCORESET associated with the first common search space is configured tobe the first CORESET or the second CORESET, the first start position isa start position of the set of the allocated resource blocks, and thenumber of first resource blocks is the number of resource blockscontinuously allocated in the set of allocated resource blocks.

(2) Also, a base station apparatus that communicates with a terminalapparatus according to an aspect of the present invention includes: atransmission unit configured to transmit an MIB that configures a firstcontrol resource set (CORESET), transmit an SIB1 that configures asecond CORESET, transmit first information that configures an initialuplink bandwidth part (UL BWP) and second information that configures anadditional UL BWP, generate a first field based on a set of resourceblocks allocated to the terminal apparatus, and transmit a first DCIformat including a generated first field in a common search space; and areception unit configured to receive a PUSCH in an active UL BWP, theactive UL BWP for the terminal apparatus being a UL BWP resulting fromactivation of either the initial UL BWP or the additional UL BWP,wherein in a case that the common search space is a first common searchspace, a first value indicated by the first field is provided based on asize of the initial UL BWP, a first start position, and the number offirst resource blocks continuously allocated, the first common searchspace is a common search space used for a random access procedure, aCORESET associated with the first common search space is configured tobe the first CORESET or the second CORESET, the first start position isa start position of the set of the allocated resource blocks, and thenumber of first resource blocks is the number of resource blockscontinuously allocated in the set of allocated resource blocks.

(3) Also, a communication method according to an aspect of the presentinvention is a communication method for a terminal apparatus including:receiving an MIB that configures a first control resource set (CORESET),receiving an SIB1 that configures a second CORESET, receiving firstinformation that configures an initial uplink bandwidth part (UL BWP)and second information that configures an additional UL BWP, andreceiving a first DCI format that schedules a PUSCH in a common searchspace; and identifying a set of allocated resource blocks based on afirst field included in the first DCI format and transmitting the PUSCHin an active UL BWP, the active UL BWP being a UL BWP resulting fromactivation of either the initial UL BWP or the additional UL BWP in acase that the common search space is a first common search space, afirst value indicated by the first field is provided based on a size ofthe initial UL BWP, a first start position, and the number of firstresource blocks continuously allocated, the first common search space isa common search space used for a random access procedure, a CORESETassociated with the first common search space is configured to be thefirst CORESET or the second CORESET, the first start position is a startposition of the set of the allocated resource blocks, and the number offirst resource blocks is the number of resource blocks continuouslyallocated in the set of allocated resource blocks.

(4) A communication method according to an aspect of the presentinvention is a communication method for a base station apparatus thatcommunicates with a terminal apparatus, the method including:transmitting an MIB that configures a first control resource set(CORESET), transmitting an SIB1 that configures a second CORESET,transmitting first information that configures an initial uplinkbandwidth part (UL BWP) and second information that configures anadditional UL BWP, generating a first field based on a set of resourceblocks allocated to the terminal apparatus, and transmitting a first DCIformat including the generated first field in a common search space; andreceiving a PUSCH in an active UL BWP, the active UL BWP for theterminal apparatus being a UL BWP resulting from activation of eitherthe initial UL BWP or the additional UL BWP in a case that the commonsearch space is a first common search space, a first value indicated bythe first field is provided based on a size of the initial UL BWP, afirst start position, and the number of first resource blockscontinuously allocated, the first common search space is a common searchspace used for a random access procedure, a CORESET associated with thefirst common search space is configured to be the first CORESET or thesecond CORESET, the first start position is a start position of the setof the allocated resource blocks, and the number of first resourceblocks is the number of resource blocks continuously allocated in theset of allocated resource blocks.

(5) An integrated circuit according to an aspect of the presentinvention is an integrated circuit that is mounted in a terminalapparatus and causes the terminal apparatus to perform: receiving an MIBthat configures a first control resource set (CORESET), receiving a SIB1that configures a second CORESET, receiving first information thatconfigures an initial uplink bandwidth part (UL BWP) and secondinformation that configures an additional UL BWP, and receiving a firstDCI format that schedules a PUSCH in a common search space; andidentifying a set of allocated resource blocks based on a first fieldincluded in the first DCI format and transmitting the PUSCH in an activeUL BWP, the active UL BWP being a UL BWP resulting from activation ofeither the initial UL BWP or the additional UL BWP in a case that thecommon search space is a first common search space, a first valueindicated by the first field is provided based on a size of the initialUL BWP, a first start position, and the number of first resource blockscontinuously allocated, the first common search space is a common searchspace used for a random access procedure, a CORESET associated with thefirst common search space is configured to be the first CORESET or thesecond CORESET, the first start position is a start position of the setof the allocated resource blocks, and the number of first resourceblocks is the number of resource blocks continuously allocated in theset of allocated resource blocks.

(6) Also, an integrated circuit according to an aspect of the presentinvention is an integrated circuit that is mounted in a base stationapparatus that communicates with a terminal apparatus, the integratedcircuit causing the base station apparatus to perform: transmitting anMIB that configures a first control resource set (CORESET), transmittingan SIB1 that configures a second CORESET, transmitting first informationthat configures an initial uplink bandwidth part (UL BWP) and secondinformation that configures an additional UL BWP, generating a firstfield based on a set of resource blocks allocated to the terminalapparatus, and transmitting a first DCI format including the generatedfirst field in a common search space; and a function of receiving aPUSCH in an active UL BWP, the active UL BWP for the terminal apparatusbeing a UL BWP resulting from activation of either the initial UL BWP orthe additional UL BWP in a case that the common search space is a firstcommon search space, a first value indicated by the first field isprovided based on a size of the initial UL BWP, a first start position,and the number of first resource blocks continuously allocated, thefirst common search space is a common search space used for a randomaccess procedure, a CORESET associated with the first common searchspace is configured to be the first CORESET or the second CORESET, thefirst start position is a start position of the set of the allocatedresource blocks, and the number of first resource blocks is the numberof resource blocks continuously allocated in the set of allocatedresource blocks.

Advantageous Effects of Invention

According to an aspect of the present invention, a base stationapparatus and a terminal apparatus can efficiently communicate with eachother.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a diagram illustrating a concept of a radio communicationsystem according to an embodiment of the present invention.

FIG. 2 is a diagram illustrating examples of an SS/PBCH block and an SSburst set according to the embodiment of the present invention.

FIG. 3 is a diagram illustrating overview configurations of uplink anddownlink slots according to the embodiment of the present invention.

FIG. 4 is a diagram illustrating a relationship among a subframe, aslot, and a mini slot in a time domain according to the embodiment ofthe present invention.

FIG. 5 is a diagram illustrating an example of a slot or a subframeaccording to the embodiment of the present invention.

FIG. 6 is a diagram illustrating an example of beam forming according tothe embodiment of the present invention.

FIG. 7 is a diagram illustrating an example of BWP configurationaccording to the embodiment of the present invention.

FIG. 8 is a diagram illustrating an example of a random access procedureof a terminal apparatus 1 according to the embodiment of the presentinvention.

FIG. 9 is a diagram illustrating an example of fields included in an RARUL grant according to the embodiment of the present invention.

FIG. 10 is a diagram illustrating an example of interpretation of an‘Msg3 PUSCH frequency resource allocation’ field according to thepresent embodiment.

FIG. 11 is a diagram illustrating an example for explaining an uplinkresource allocation type 1 for BWPs according to the present embodiment.

FIG. 12 is a diagram illustrating an example in which an RIV iscalculated, according to the embodiment of the present invention.

FIG. 13 is a diagram illustrating an example of allocation of SSBindexes to PRACH occasions according to the present embodiment.

FIG. 14 is a flow diagram illustrating an example of a random accessprocedure of a MAC entity according to the embodiment of the presentinvention.

FIG. 15 is an overview block diagram illustrating a configuration of theterminal apparatus 1 according to the embodiment of the presentinvention.

FIG. 16 is an overview block diagram illustrating a configuration of abase station apparatus 3 according to the embodiment of the presentinvention.

DESCRIPTION OF EMBODIMENTS

Embodiments of the present invention will be described below.

FIG. 1 is a conceptual diagram of a radio communication system accordingto the present embodiment. In FIG. 1, the radio communication systemincludes a terminal apparatus 1A, a terminal apparatus 1B, and a basestation apparatus 3. Hereinafter, the terminal apparatus 1A and theterminal apparatus 1B will also be referred to as a terminal apparatus1.

The terminal apparatus 1 will also be referred to as a user terminal, amobile station device, a communication terminal, a mobile device, aterminal, User Equipment (UE), or a Mobile Station (MS). The basestation apparatus 3 will also be referred to as a radio base stationapparatus, a base station, a radio base station, a fixed station, aNodeB (NB), an evolved NodeB (eNB), a Base Transceiver Station (BTS), aBase Station (BS), an NR NodeB (NR NB), NNB, a Transmission andReception Point (TRP), or a gNB. The base station apparatus 3 mayinclude a core network apparatus. Also, the base station apparatus 3 mayinclude one or a plurality of transmission reception points 4. At leasta part of functions/processing of the base station apparatus 3 describedbelow may be functions/processing of each of the transmission receptionpoints 4 included in the base station apparatus 3. The base stationapparatus 3 may serve the terminal apparatus 1 using a communicationrange (communication area) controlled by the base station apparatus 3 asone or a plurality of cells. Also, the base station apparatus 3 mayserve the terminal apparatus 1 using a communication range(communication area) controlled by one or a plurality of transmissionreception points 4 as one or a plurality of cells. Also, one cell may besplit into a plurality of beamed areas, and the terminal apparatus 1 maybe served in each of the beamed areas. Here, the beamed areas may beidentified based on indexes of beams used in beam forming or indexes ofprecoding.

A radio communication link from the base station apparatus 3 to theterminal apparatus 1 will be referred to as a downlink. A radiocommunication link from the terminal apparatus 1 to the base stationapparatus 3 will be referred to as an uplink.

In FIG. 1, Orthogonal Frequency Division Multiplexing (OFDM) including aCyclic Prefix (CP), Single-Carrier Frequency Division Multiplexing(SC-FDM), Discrete Fourier Transform Spread OFDM (DFT-S-OFDM), andMulti-Carrier Code Division Multiplexing (MC-CDM) are used for the radiocommunication between the terminal apparatus 1 and the base stationapparatus 3.

Also, Universal-Filtered Multi-Carrier (UFMC), Filtered OFDM (F-OFDM),OFDM multiplied by a window function (Windowed OFDM), and Filter-BankMulti-Carrier (FBMC) may be used for radio communication between theterminal apparatus 1 and the base station apparatus 3 in FIG. 1.

Note that although the present embodiment will be described with OFDMsymbols using OFDM as a transmission scheme, cases in which theaforementioned other transmission schemes are used are also included inthe present invention.

Also, in the radio communication between the terminal apparatus 1 andthe base station apparatus 3, a CP may not be used, or theaforementioned transmission scheme with zero padding may be used insteadof the CP in FIG. 1. Moreover, the CP or zero padding may be added bothforward and backward.

An aspect of the present embodiment may be operated in carrieraggregation or dual connectivity with a Radio Access Technology (RAT)such as LTE or LTE-A/LTE-A Pro. At this time, the aspect may be used ina part or all of cells or cell groups, carriers or carrier groups (forexample, Primary Cells (PCell), secondary cells (SCell), PrimarySecondary Cells (PSCell), Master Cell Groups (MCG), Secondary CellGroups (SCG), or the like). Moreover, the aspect may be used in astand-alone manner and may be independently operated. In dualconnectivity operation, a Special Cell (SpCell) will be referred to as aPCell of an MCG or a PSCell of an SCG in accordance with which of an MCGand an SCG a Medium Access Control (MAC) entity is associated with,respectively. In a case that the dual connectivity operation is notemployed, the Special Cell (SpCell) will be referred to as PCell. TheSpecial Cell (SpCell) supports PUCCH transmission and contention basedrandom access.

In the present embodiment, one or a plurality of serving cells may beconfigured for the terminal apparatus 1. The plurality of configuredserving cells may include one primary cell and one or a plurality ofsecondary cells. The primary cell may be a serving cell on which aninitial connection establishment procedure has been performed, a servingcell for which a connection re-establishment procedure has been started,or a cell indicated as a primary cell in a handover procedure. One or aplurality of secondary cells may be configured at or after establishmentof Radio Resource Control (RRC) connection. However, the plurality ofconfigured serving cells may include one primary secondary cell. Theprimary secondary cell may be a secondary cell capable of performinguplink transmission of control information, from among one or aplurality of secondary cells configured for the terminal apparatus 1.Also, two types of serving cell subsets, namely a master cell group anda secondary cell group may be configured for the terminal apparatus 1.The master cell group may include one primary cell and zero or moresecondary cells. The secondary cell group may include one primarysecondary cell and zero or more secondary cells.

Time Division Duplex (TDD) and/or Frequency Division Duplex (FDD) may beapplied to the radio communication system according to the presentembodiment. The Time Division Duplex (TDD) scheme or the FrequencyDivision Duplex (FDD) scheme may be applied to all of the plurality ofcells. Cells to which the TDD scheme is applied and cells to which theFDD scheme is applied may be aggregated. The TDD scheme may be referredto as an unpaired spectrum operation. The FDD scheme may be referred toas a paired spectrum operation.

A carrier corresponding to a serving cell in the downlink will bereferred to as a downlink component carrier (or a downlink carrier). Acarrier corresponding to a serving cell in the uplink will be referredto as an uplink component carrier (or an uplink carrier). A carriercorresponding to a serving cell in a sidelink will be referred to as asidelink component carrier (or a sidelink carrier). The downlinkcomponent carrier, the uplink component carrier, and/or the sidelinkcomponent carrier will be collectively referred to as a componentcarrier (or a carrier).

Physical channels and physical signals according to the presentembodiment will be described.

In FIG. 1, the following physical channels are used for the radiocommunication between the terminal apparatus 1 and the base stationapparatus 3.

-   -   Physical Broadcast CHannel (PBCH)    -   Physical Downlink Control Channel (PDCCH)    -   Physical Downlink Shared Channel (PDSCH)    -   Physical Uplink Control CHannel (PUCCH)    -   Physical Uplink Shared CHannel (PUSCH)    -   Physical Random Access CHannel (PRACH)

The PBCH is used to provide a notification of essential informationblocks (a Master Information Block (MIB), an Essential Information Block(EIB), and a Broadcast Channel (BCH)) which includes important systeminformation needed by the terminal apparatus 1.

Also, the PBCH may be used to provide a notification of a time index ina period of a synchronization signal block (also referred to as anSS/PBCH block). Here, the time index is information indicating an indexof a synchronization signal in the cell and the PBCH. In a case that theSS/PBCH block is transmitted using an assumption of three transmissionbeams (Quasi Co-Location (QCL) regarding transmission filterconfiguration and reception space parameters), for example, the timeindex may indicate a time order in a predefined period or a configuredperiod. Also, the terminal apparatus may recognize a difference in timeindexes as a difference in transmission beams.

The PDCCH is used to transmit (or carry) Downlink Control Information(DCI) in downlink radio communication (radio communication from the basestation apparatus 3 to the terminal apparatus 1). Here, one or aplurality of pieces of DCI (which may be referred to as DCI formats) aredefined for the transmission of downlink control information. In otherwords, a field for the downlink control information is defined as DCIand is mapped to information bits. The PDCCH is transmitted in a PDCCHcandidate. The terminal apparatus 1 monitors a set of PDCCH candidatesin the serving cell. The monitoring means an attempt to decode the PDCCHin accordance with a certain DCI format.

For example, the following DCI formats may be defined.

-   -   DCI format 0_0    -   DCI format 0_1    -   DCI Format 1_0    -   DCI Format 1_1    -   DCI Format 2_0    -   DCI Format 2_1    -   DCI Format 2_2    -   DCI Format 2_3

The DCI format 0_0 may include information indicating schedulinginformation of the PUSCH (frequency domain resource allocation and timedomain resource allocation).

The DCI format 0_1 may include information indicating schedulinginformation of the PUSCH (frequency domain resource allocation and timedomain resource allocation), information indicating a BandWidth Part(BWP), a Channel State Information (CSI) request, a Sounding ReferenceSignal (SRS) request, and information regarding an antenna port.

The DCI format 1_0 may include information indicating schedulinginformation of the PDSCH (frequency domain resource allocation and timedomain resource allocation).

The DCI format 1_1 may include information indicating schedulinginformation of the PDSCH (frequency domain resource allocation and timedomain resource allocation), information indicating a BandWidth Part(BWP), a Transmission Configuration Indication (TCI), and informationregarding an antenna port.

The DCI format 2_0 is used to notify a slot format of one or a pluralityof slots. The slot format is defined by each OFDM symbol in the slotbeing categorized into any of downlink, flexible, and uplink symbol. Ina case that a slot format is 28, for example, DDDDDDDDDDDDFU is appliedto fourteen OFDM symbols in the slot for which the slot format 28 hasbeen indicated. Here, D denotes a downlink symbol, F denotes a flexiblesymbol, and U denotes an uplink symbol. Note that the slot will bedescribed later.

The DCI format 2_1 is used to notify, to the terminal apparatus 1,physical resource blocks and OFDM symbols that may be assumed not to betransmitted. Note that this information may be referred to as apreemption indication (intermittent transmission indication).

The DCI format 2_2 is used to transmit a Transmit Power Control (TPC)command for the PUSCH and the PUSCH.

The DCI format 2_3 is used to transmit a group of TPC commands forsounding reference signals (SRS) transmission performed by one or aplurality of terminal apparatuses 1. An SRS request may be transmittedalong with the TPC command. In addition, the SRS request and the TPCcommand may be defined in the DCI format 2_3 for the uplink with neitherthe PUSCH nor the PUCCH or for the uplink in which SRS transmissionpower control is not linked to PUSCH transmission power control.

The DCI for the downlink will also be referred to as a downlink grant ordownlink assignment. Here, the DCI for the uplink will also be referredto as an uplink grant or uplink assignment.

A Cyclic Redundancy Check (CRC) parity bit added to a DCI formattransmitted by one PDCCH is scrambled with a Cell-Radio NetworkTemporary Identifier (C-RNTI), a Configured Scheduling-Radio NetworkTemporary Identifier (CS-RNTI), a Random Access-Radio Network TemporaryIdentity (RA-RNTI), or a Temporary C-RNTI. The C-RNTI and the CS-RNTIare identifiers for identifying a terminal apparatus within a cell. TheTemporary C-RNTI is an identifier for identifying the terminal apparatus1 that has transmitted a random access preamble during a contentionbased random access procedure.

The C-RNTI (an identifier (identification information) of the terminalapparatus) is used to control the PDSCH or the PUSCH in one or aplurality of slots. The CS-RNTI is used to periodically allocate thePDSCH or PUSCH resources. The Temporary C-RNTI (TC-RNTI) is used tocontrol PDSCH transmission or PUSCH transmission in one or a pluralityof slots. The Temporary C-RNTI is used to schedule re-transmission of arandom access message 3 and transmission of a random access message 4.RA-RNTI (random access response identification information) isdetermined in accordance with position information of a frequency and atime of a physical random access channel through which a random accesspreamble has been transmitted.

The PUCCH is used to transmit Uplink Control Information (UCI) in uplinkradio communication (radio communication from the terminal apparatus 1to the base station apparatus 3). Here, the uplink control informationmay include Channel State Information (CSI) used to indicate a downlinkchannel state. Also, the uplink control information may include aScheduling Request (SR) used to request a UL-SCH resource. The uplinkcontrol information may include a Hybrid Automatic Repeat requestACKnowledgement (HARQ-ACK). The HARQ-ACK may indicate an HARQ-ACK fordownlink data (Transport block, Medium Access Control Protocol DataUnit: MAC PDU, Downlink-Shared Channel: DL-SCH).

The PDSCH is used to transmit downlink data (Downlink Shared Channel:DL-SCH) from a medium access (Medium Access Control: MAC) layer. Also,in a case of the downlink, the PDSCH is used to transmit SystemInformation (SI), a Random Access Response (RAR), and the like.

The PUSCH may be used to transmit the HARQ-ACK and/or the CSI along withuplink data (Uplink Shared CHannel: UL-SCH) or uplink data from the MAClayer. Also, the PUSCH may be used to transmit only the CSI or only theHARQ-ACK and the CSI. In other words, the PUSCH may be used to transmitonly the UCI.

Here, the base station apparatus 3 and the terminal apparatus 1 exchange(transmit and receive) signals in a higher layer. For example, the basestation apparatus 3 and the terminal apparatus 1 may transmit andreceive Radio Resource Control (RRC) signaling (also referred to as aRadio Resource Control (RRC) message or Radio Resource Control (RRC)information) in a Radio Resource Control (RRC) layer. Also, the basestation apparatus 3 and the terminal apparatus 1 may transmit andreceive a Medium Access Control (MAC) element in a MAC layer. Here, theRRC signaling and/or the MAC control element will also be referred to ashigher layer signaling. The higher layer here means a higher layer thanthe physical layer and may thus include one or a plurality of the MAClayer, the RRC layer, the RLC layer, the PDCP layer, a Non AccessStratum (NAS) layer, and the like. For example, the higher layer mayinclude one or a plurality of the RRC layer, the RLC layer, the PDCPlayer, the NAS layer, and the like in the processing of the MAC layer.

The PDSCH or the PUSCH may be used to transmit the RRC signaling and theMAC control element. Here, the RRC signaling transmitted from the basestation apparatus 3 in the PDSCH may be signaling common to a pluralityof terminal apparatuses 1 in a cell. Also, the RRC signaling transmittedfrom the base station apparatus 3 may be signaling dedicated for aspecific terminal apparatus 1 (also referred to as dedicated signaling).In other words, terminal apparatus specific (UE specific) informationmay be transmitted using signaling dedicated for a specific terminalapparatus 1. Also, the PUSCH may be used to transmit a UE capability inthe uplink.

In FIG. 1, the following downlink physical signals are used for downlinkradio communication. Here, the downlink physical signals are not used totransmit information output from the higher layers but are used by thephysical layer.

-   -   Synchronization signal (SS)    -   Reference Signal (RS)

The synchronization signal may include a Primary Synchronization Signal(PSS) and a Secondary Synchronization Signal (SSS). A cell ID may bedetected using the PSS and the SSS.

The synchronization signal is used by the terminal apparatus 1 toestablish synchronization in a frequency domain and a time domain in thedownlink. Here, the synchronization signal may be used by the terminalapparatus 1 to select precoding or a beam in precoding or beamformingperformed by the base station apparatus 3. Note that the beam may bereferred to as a transmission or reception filter configuration, or aspace domain transmission filter or space domain reception filter.

The reference signal is used by the terminal apparatus 1 to performchannel compensation on a physical channel. Here, the reference signalmay also be used by the terminal apparatus 1 to calculate the downlinkCSI. Also, the reference signal may be used for a numerology such asradio parameters or subcarrier spacing or may be used for finesynchronization that allows FFT window synchronization to be achieved.

According to the present embodiment, any one or a plurality of thefollowing downlink reference signals are used.

-   -   Demodulation Reference Signal (DMRS)    -   Channel State Information Reference Signal (CSI-RS)    -   Phrase Tracking Reference Signal (PTRS)    -   Tracking Reference Signal (TRS)

The DMRS is used to demodulate a modulated signal. Note that two typesof reference signals, namely a reference signal for demodulating thePBCH and a reference signal for demodulating the PDSCH may be defined inthe DMRS, or the both may be referred to as the DMRS. The CSI-RS may beused for measurement of Channel State Information (CSI) and beammanagement, and a periodic, semipersistent, or non-periodic CSIreference signal transmission method is applied thereto. Non-Zero Power(NZP) CSI-RS and Zero Power (ZP) CSI-RS with zero transmission power (orreception power) may be defined for the CSI-RS. Here, the ZP CSI-RS maybe defined as a CSI-RS resource with zero transmission power or that isnot to be transmitted. The PTRS is used to track a phase in a time axisfor the purpose of securing a frequency offset caused by phase noise.The TRS is used to secure Doppler shift during high-speed moving. Notethat the TRS may be used as one configuration of the CSI-RS. Forexample, a radio resource may be configured using one port CSI-RS as theTRS.

In the present embodiment, any one or a plurality of the followinguplink reference signals are used.

-   -   Demodulation Reference Signal (DMRS)    -   Phrase Tracking Reference Signal (PTRS)    -   Sounding Reference Signal (SRS)

The DMRS is used to demodulate a modulated signal. Note that two typesof reference signals, namely a reference signal for demodulating thePUCCH and a reference signal for demodulating the PUSCH may be definedin the DMRS, or the both may be referred to as the DMRS. The SRS is usedfor measurement of uplink channel state information (CSI), channelsounding, and beam management. The PTRS is used to track a phase in atime axis for the purpose of securing a frequency offset caused by phasenoise.

The downlink physical channels and/or the downlink physical signals willcollectively be referred to as a downlink signal. The uplink physicalchannels and/or the uplink physical signals will collectively bereferred to as an uplink signal. The downlink physical channels and/orthe uplink physical channels will collectively be referred to as aphysical channel. The downlink physical signals and/or the uplinkphysical signals will collectively be referred to as a physical signal.

The BCH, the UL-SCH, and the DL-SCH are transport channels. A channelused in the Medium Access Control (MAC) layer will be referred to as atransport channel. A unit of the transport channel used in the MAC layerwill also be referred to as a Transport Block (TB) and/or a MAC ProtocolData Unit (PDU). A Hybrid Automatic Repeat reQuest (HARM) is controlledfor each transport block in the MAC layer. The transport block is a unitof data that the MAC layer delivers to the physical layer. In thephysical layer, the transport block is mapped to a codeword, and codingprocessing is performed for each codeword.

FIG. 2 is a diagram illustrating examples of an SS/PBCH block (alsoreferred to as a synchronization signal block, an SS block, or SSB) andan SS burst set (also referred to as a synchronization signal burst set)according to the present embodiment. FIG. 2 illustrates an example inwhich two SS/PBCH blocks are included in the SS burst set periodicallytransmitted and each SS/PBCH block includes continuous 4 OFDM symbols.

The SS/PBCH block is a unit block including at least synchronizationsignals (PSS, SSS) and/or the PBCH. Transmission of the signals/channelincluded in the SS/PBCH block will be expressed as transmission of theSS/PBCH block. In a case that the base station apparatus 3 transmits thesynchronization signals and/or the PBCH using one or a plurality ofSS/PBCH blocks in the SS burst set, the base station apparatus 3 may usea downlink transmission beam independent for each SS/PBCH block.

In FIG. 2, the PSS, the SSS, and the PBCH are time/frequency-multiplexedin one SS/PBCH block. However, the order in which the PSS, the SSS,and/or the PBCH is multiplexed in the time domain may differ from theone in the example illustrated in FIG. 2.

The SS burst set may be periodically transmitted. For example, a periodto be used for an initial access and a period configured for theconnected terminal apparatus (Connected or RRC_Connected) may bedefined. Also, the period configured for the connected terminalapparatus (Connected or RRC_Connected) may be configured in the RRClayer. In addition, the period configured for the connected terminal(Connected or RRC_Connected) may be a period of a radio resource in thetime domain with a potential of transmission, and in practice, the basestation apparatus 3 may determine whether to perform transmission. Also,the period used for the initial access may be predefined inspecifications or the like.

The SS burst set may be determined based on a System Frame Number (SFN).Also, a start position (boundary) of the SS burst set may be determinedbased on the SFN and the period.

An SSB index (which may also be referred to as an SSB/PBCH block index)is allocated to the SS/PBCH block in accordance with a temporal positionin the SS burst set. The terminal apparatus 1 calculates the SSB indexbased on information of the PBCH and/or information of the referencesignals included in the detected SS/PBCH block.

The same SSB index is allocated to SS/PBCH blocks with the same relativetime in each SS burst set among a plurality of SS burst sets. TheSS/PBCH blocks with the same relative time in each SS burst set amongthe plurality of SS burst sets may be assumed to be QCL (or to which thesame downlink transmission beam has been applied). Also, antenna portsof the SS/PBCH blocks with the same relative time in each SS burst setamong the plurality of SS burst sets may be assumed to be QCL in regardto an average delay, Doppler shift, and a spatial correlation.

SS/PBCH blocks to which the same SSB index is allocated in a period of acertain SS burst set may be assumed to be QCL in regard to an averagedelay, an average gain, Doppler spread, Doppler shift, and a spatialcorrelation. Settings corresponding to one or a plurality of SS/PBCHblocks (or which may be reference signals) that are QCL may be referredto as QCL configurations.

The number of SS/PBCH blocks (which may also be referred to as thenumber of SS blocks or the number of SSBs), may be defined as the numberof SS/PBCH blocks in an SS burst, an SS burst set, or an SS/PBCH blockperiod, for example. Also, the number of SS/PBCH blocks may indicate thenumber of beam groups for selecting a cell in the SS burst, the SS burstset, or the SS/PBCH block period. Here, the beam groups may be definedas the number of different SS/PBCH blocks or the number of differentbeams included in the SS burst, the SS burst set, or the SS/PBCH blockperiod.

The reference signals described below in the present embodiment includea downlink reference signal, a synchronization signal, an SS/PBCH block,a downlink DM-RS, a CSI-RS, an uplink reference signal, an SRS, and/oran uplink DM-RS. For example, the downlink reference signal, thesynchronization signal, and/or the SS/PBCH block may be referred to asreference signals. The reference signals used in the downlink include adownlink reference signal, a synchronization signal, an SS/PBCH block, adownlink DM-RS, a CSI-RS, and the like. The reference signals used inthe uplink include an uplink reference signal, an SRS, an uplink DM-RS,and/or the like.

In addition, the reference signal may also be used for Radio ResourceMeasurement (RRM). The reference signal may also be used for beammanagement.

The beam management may be a procedure performed by the base stationapparatus 3 and/or the terminal apparatus 1 to match directionalitybetween an analog and/or digital beam in a transmission apparatus (thebase station apparatus 3 in the case of the downlink, or the terminalapparatus 1 in the case of the uplink) and an analog and/or digital beamof a reception apparatus (the terminal apparatus 1 in the case of thedownlink, or the base station apparatus 3 in the case of the uplink) andacquire a beam gain.

Note that the following procedures may be included as a procedure ofconfiguring, configuration, or establishing beam pairing.

-   -   Beam selection    -   Beam refinement    -   Beam recovery

For example, the beam selection may be a procedure for selecting a beamin communication between the base station apparatus 3 and the terminalapparatus 1. Also, the beam refinement may be a procedure of selecting abeam having a higher gain or changing a beam to an optimum beam betweenthe base station apparatus 3 and the terminal apparatus 1 according tothe movement of the terminal apparatus 1. The beam recovery may be aprocedure of re-selecting the beam in a case that the quality of acommunication link is degraded due to blockage caused by a blockingobject, passing of a person, or the like in communication between thebase station apparatus 3 and the terminal apparatus 1.

The beam selection and the beam refinement may be included in the beammanagement. The beam recovery may include the following procedures.

-   -   Detection of beam failure    -   Discovery of new beam    -   Transmission of beam recovery request    -   Monitoring of response to beam recovery request

For example, a Reference Signal Received Power (RSRP) of the SSSincluded in the CSI-RS or the SS/PBCH block may be used, or the CSI maybe used, in a case that a transmission beam for the base stationapparatus 3 is selected in the terminal apparatus 1. In addition, aCSI-RS Resource Index (CRI) may be used as a report to the base stationapparatus 3, or an index indicated by a sequence of demodulationreference signals (DMRS) used for demodulating the PBCH and/or the PBCHincluded in the SS/PBCH block may be used.

Also, the base station apparatus 3 indicates a time index of the CRI orthe SS/PBCH in a case that a beam is indicated for the terminalapparatus 1, and the terminal apparatus 1 performs reception based onthe indicated time index of the CRI or the SS/PBCH. At this time, theterminal apparatus 1 may configure a space filter based on the indicatedtime index of the CRI or the SS/PBCH and may perform reception. Inaddition, the terminal apparatus 1 may perform reception using theassumption of a Quasi Co-Location (QCL). An expression that a certainsignal (such as an antenna port, a synchronization signal, or areference signal) is “QCL” with another signal (such as an antenna port,a synchronization signal, or a reference signal) or an expression that“an assumption of QCL is used” can be interpreted as having a meaningthat the certain signal is associated with another signal.

In a case that a Long Term Property of a channel on which a certainsymbol in a certain antenna port is carried can be estimated from achannel on which a certain symbol in the other antenna port is carried,it is possible to state that the two antenna ports are QCL. The LongTerm Property of the channel includes one or a plurality of delayspread, Doppler spread, Doppler shift, an average gain, and an averagedelay. In a case that an antenna port 1 and an antenna port 2 are QCL inregard to an average delay, for example, this means that a receptiontiming for the antenna port 2 can be estimated from a reception timingfor the antenna port 1.

The QCL can also be expanded to beam management. For this purpose,spatially expanded QCL may be newly defined. For example, the Long termproperty of a channel on the assumption of QCL in the space domain maybe an arrival angle in a radio link or the channel (such as an Angle ofArrival (AoA) or a Zenith angle of Arrival (ZoA)) and/or an angle spread(for example, Angle Spread of Arrival (ASA) or a Zenith angle Spread ofArrival (ZSA)), a transmission angle (such as AoD or ZoD) or an anglespread of the transmission angle (for example, an Angle Spread ofDeparture (ASD) or a Zenith angle Spread of Departure (ZSD)), SpatialCorrelation, or a reception space parameter.

In a case that the antenna port 1 and the antenna port 2 can be regardedas being QCL in regard to the reception space parameter, for example,this means that a reception beam for receiving a signal from the antennaport 2 can be estimated from a reception beam (reception space filter)for receiving a signal from the antenna port 1.

As QCL types, combinations of long term properties that may be QCL maybe defined. For example, the following types may be defined.

-   -   Type A: Doppler shift, Doppler spread, average delay, delay        spread    -   Type B: Doppler shift, Doppler spread    -   Type C: Average delay, Doppler shift    -   Type D: Receiving space parameter

For the aforementioned QCL types, an assumption of QCL between one ortwo reference signals and the PDCCH or the PDSCH DMRS in the RRC and/orthe MAC layer and/or the DCI may be configured and/or indicated as aTransmission Configuration Indication (TCI). In a case that an index #2of the SS/PBCH block and a QCL type A+QCL type B are configured and/orindicated as one state of the TCI in a case that the terminal apparatus1 receives the PDCCH, for example, the terminal apparatus 1 may receivethe DMRS of the PDCCH by regarding it as Doppler shift, Doppler spreadin a case of receiving the index #2 of the SS/PBCH block, an averagedelay, delay spread, a reception space parameter, and a channel longterm property and may perform synchronization and carrier pathestimation, in a case that the terminal apparatus 1 receives the PDCCHDMRS. At this time, a reference signal (the SS/PBCH block in theaforementioned example) indicated by the TCI may be referred to as asource reference signal, and a reference signal (the PDCCH DMRS in theaforementioned example) affected by a long term property estimated fromthe long term property of the channel in a case that the sourcereference signal is received may be referred to as a target referencesignal. Also, one or a plurality of TCI states and a combination of asource reference signal and a QCL type for each state may be configuredwith the RRC, and the TCI may be indicated in the MAC layer or the DCIfor the terminal apparatus 1.

Operations of the base station apparatus 3 and the terminal apparatus 1equivalent to the beam management may be defined through assumption ofQCL in the space domain and with a radio resource (time and/orfrequency) as beam management and beam indication/report by this method.

Hereinafter, the subframe will be described. The subframe referred inthe present embodiment may also be referred to as a resource unit, aradio frame, a time section, a time interval, or the like.

FIG. 3 is a diagram illustrating an example of overview configurationsof uplink and downlink slots according to a first embodiment of thepresent invention. Each of the radio frames is 10 ms in length. Also,each of the radio frames includes ten subframes and W slots. Also, oneslot includes X OFDM symbols. In other words, the length of one subframeis 1 ms. For slot, a time length is defined based on subcarrier spacing.For example, in a case of OFDM symbol subcarrier spacing of 15 kHz and aNormal Cyclic Prefix (NCP), X=7 or X=14, which correspond to 0.5 ms and1 ms, respectively. Also, in a case of subcarrier spacing of 60 kHz, X=7or X=14, which correspond to 0.125 ms and 0.25 ms, respectively. Inaddition, in a case that X=14, for example, W=10 in a case that thesubcarrier spacing is 15 kHz, and W=40 in a case that the subcarrierspacing is 60 kHz. FIG. 3 illustrates a case in which X=7 as an example.Note that expansion can similarly be performed even in a case that X=14.Also, the uplink slot is similarly defined, and the downlink slot andthe uplink slot may be separately defined. Also, a bandwidth of the cellin FIG. 3 may be defined as a BandWidth Part (BWP). Moreover, the slotmay be defined as a Transmission Time Interval (TTI). The slot may notbe defined as the TTI. The TTI may be a transmission period of thetransport block.

A signal or a physical channel transmitted in each slot may be expressedby a resource grid. The resource grid is defined by a plurality ofsubcarriers and a plurality of OFDM symbols for each numerology(subcarrier spacing and cyclic prefix length) and each carrier. Thenumber of subcarriers configuring one slot depends on each of thedownlink and uplink bandwidths of a cell. Each element in the resourcegrid will be referred to as a resource element. The resource element maybe identified using a subcarrier number and an OFDM symbol number.

The resource grid is used to express mapping of resource elements of acertain physical downlink channel (such as a PDSCH) or an uplink channel(such as a PUSCH). In a case that the subcarrier spacing is 15 kHz, forexample, the number X of OFDM symbols included in the subframe=14, andin the case of the NCP, one physical resource block is defined byfourteen continuous OFDM symbols in the time domain and 12*Nmaxcontinuous subcarriers in the frequency domain. Nmax is the maximumnumber of resource blocks determined by the subcarrier spacingconfiguration μ, which will be described later. In other words, theresource grid includes (14*12*Nmax, μ) resource elements. Extended CP(ECP) is supported only by subcarrier spacing of 60 kHz, one physicalresource block is defined by 12 (the number of OFDM symbols included inone slot)*4(the number of slots included in one subframe)=48 continuousOFDM symbols in the time domain and 12*Nmax, μ continuous subcarriers inthe frequency domain, for example. In other words, the resource gridincludes (48*12*Nmax, μ) resource elements.

As resource blocks, reference resource blocks, common resource blocks,physical resource blocks, and virtual resource blocks are defined. Oneresource block is defined as twelve continuous subcarriers in thefrequency domain. The reference resource blocks are common to allsubcarriers, the resource blocks may be configured with subcarrierspacing of 15 kHz, for example, and may be numbered in an ascendingorder. A subcarrier index 0 in a reference resource block index 0 may bereferred to as a reference point A (point A) (which may simply bereferred to as a “reference point”). The common resource blocks areresource blocks numbered in an ascending order from 0 at each subcarrierspacing configuration μ from the reference point A. The aforementionedresource grid is defined by the common resource blocks. The physicalresource blocks are resource blocks included in a bandwidth part (BWP),which will be described later, and numbered in an ascending order from0, and the physical resource blocks are resource blocks included in abandwidth part (BWP) and numbered in an ascending order from 0. Acertain physical uplink channel is first mapped to a virtual resourceblock. Thereafter, the virtual resource block is mapped to a physicalresource block. Hereinafter, the resource block may be a virtualresource block, a physical resource block, a common resource block, or areference resource block.

Next, the subcarrier spacing configuration μ will be described. Asdescribed above, one or a plurality of OFDM numerologies are supportedby the NR. For a certain BWP, the subcarrier spacing configuration μ(μ=0, 1, . . . , 5) and the cyclic prefix length are provided in ahigher layer relative to a downlink BWP and is provided in a higherlayer for an uplink BWP. In a case that μ is provided here, thesubcarrier spacing Δf is provided as Δf=2{circumflex over ( )}μ·15(kHz).

With the subcarrier spacing configuration μ, slots are counted in anascending order from 0 to N{circumflex over ( )}{subframe, μ}_{slot}−1in the subframe and are counted in an ascending order from 0 toN″{frame, μ}_{slot}−1 in the frame. based on the slot configuration andthe cyclic prefix, N{circumflex over ( )}{slot}_{symb} continuous OFDMsymbols are present in a slot. N{circumflex over ( )}{slot}_{symb} is14. The start of the slot n{circumflex over ( )}{μ}_{s} in a subframe isaligned with the start of the n{circumflex over ( )}{μ}_{s}N{circumflexover ( )}{slot}_{symb}-th OFDM symbol in the same subframe in terms ofthe time.

Next, a subframe, a slot, and a mini-slot will be described. FIG. 4 is adiagram illustrating a relationship among the subframe, the slot, andthe mini-slot in the time domain. As illustrated in the drawing, threetypes of time units are defined. The subframe is 1 ms regardless of thesubcarrier spacing, the number of OFDM symbols included in the slot is 7or 14, and the slot length differs depending on the subcarrier spacing.Here, in a case of the subcarrier spacing of 15 kHz, fourteen OFDMsymbols are included in one subframe. The downlink slot may be referredto as a PDSCH mapping type A. The uplink slot may be referred to as aPUSCH mapping type A.

The mini-slot (which may be referred to as a sub-slot) is a time unitincluding a smaller number of OFDM symbols than the OFDM symbolsincluded in the slot. In the drawing, a case in which the mini-slotincludes two OFDM symbols is illustrated as an example. The OFDM symbolsin the mini-slot may coincide with the OFDM symbol timing configuringthe slot. Note that a minimum unit of scheduling may be a slot or amini-slot. Moreover, allocating of a mini-slot may be referred to asnon-slot-based scheduling. In addition, an operation in which amini-slot is scheduled may be expressed as an operation in which aresource with fixed data start position in regard to a relative timeposition with respect to a reference signal is scheduled. The downlinkmini-slot may be referred to as a PDSCH mapping type B. The uplinkmini-slot may be referred to as a PUSCH mapping type B.

FIG. 5 is a diagram illustrating an example of a slot format. Here, acase in which the slot length is 1 ms at a subcarrier spacing of 15 kHzis illustrated as an example. In the drawing, D denotes the downlinkwhile U denotes the uplink. As illustrated in the drawing, a certaintime section (for example, a minimum time section that has to beallocated to one UE in a system, for example) may include one or aplurality of:

-   -   Downlink symbol    -   Flexible symbol    -   Uplink symbol.

Note that proportions thereof may be defined in advance as a slotformat. Also, the proportions thereof may be defined by the number ofdownlink OFDM symbols included in a slot or may be defined by a startposition and an end position in a slot. Also, the proportions thereofmay be defined by uplink OFDM symbols included in a slot, the number ofDFT-S-OFDM symbols, or a start position and an end position in a slot.Note that an operation in which a slot is scheduled may be expressed asan operation in which a resource with a fixed slot boundary in terms ofrelative time position with respect to a reference signal is scheduled.

The terminal apparatus 1 may receive a downlink signal or a downlinkchannel with a downlink symbol or a flexible symbol. The terminalapparatus 1 may transmit an uplink signal or a downlink channel with anuplink symbol or a flexible symbol.

FIG. 5(a) is an example used entirely for downlink transmission in acertain time section (which may be referred to as a minimum unit of timeresources that can be allocated to 1 UE, for example, or may be referredto as a time unit or the like; Also, a plurality of minimum units oftime resources may be referred to as a time unit), and in FIG. 5(b),uplink scheduling is performed via a PDCCH, for example, with a firsttime resource, and an uplink signal is transmitted via a flexible symbolincluding a PDCCH processing delay, a downlink to uplink switching time,and generation of the transmission signal. FIG. 5(c) is used for PDCCHand/or downlink PDSCH transmission with a first time resource and isused for PUSCH or PUCCH transmission via a processing delay, a downlinkto uplink switching time, and a gap for generating a transmissionsignal. Here, the uplink signal may be used to transmit HARQ-ACK and/orCSI, that is, UCI in one example. FIG. 5(b) is used for PDCCH and/orPDSCH transmission with a first time resource and is used for uplinkPUSCH and/or PUCCH transmission via a processing delay, a downlink touplink switching time, and a gap for generating a transmission signal.Here, the uplink signal may be used to transmit uplink data, that is,UL-SCH in one example. FIG. 5(e) is an example used entirely for uplinktransmission (PUSCH or PUCCH).

The aforementioned downlink part and uplink part may include a pluralityof OFDM symbols similarly to those in the LTE.

FIG. 6 is a diagram illustrating an example of beam forming. A pluralityof antenna elements are connected to one transceiver unit (TXRU) 50, aphase is controlled by a phase shifter 51 for each antenna element, anda beam can be directed to an arbitrary direction with respect to atransmission signal by transmitting it from each antenna element 52.Typically, the TXRU may be defined as an antenna port, and only theantenna port may be defined for the terminal apparatus 1. Since it ispossible to direct directionality to the arbitrary direction bycontrolling the phase shifter 51, the base station apparatus 3 cancommunicate with the terminal apparatus 1 using a beam with a high gain.

Hereinafter, a band portion (Bandwidth part) will be described. The BWPwill also be referred to as a carrier BWP. The BWP may be configured foreach of the downlink and the uplink. The BWP is defined as a group ofcontinuous physical resources selected from continuous subsets in acommon resource block. For the terminal apparatus 1, up to four BWPs foreach of which one downlink carrier BWP (DL BWP) is activated in acertain time may be configured. For the terminal apparatus 1, up to fourBWPs for each of which one uplink carrier BWP (UL BWP) is activated in acertain time may be configured. In a case of carrier aggregation, theBWPs may be configured in each serving cell. At this time, the fact thatone BWP has been configured in a certain serving cell may be expressedas a fact that no BWP has been configured. Also, the fact that two ormore BWPs have been configured may be expressed as a fact that the BWPhas been configured.

MAC Entity Operation

There is always one active (activated) BWP in an activated serving cell.BWP switching for a certain serving cell is used to activate an inactive(deactivated) BWP and deactivate an active (activated) BWP. The BWPswitching for a certain serving cell is controlled by a PDCCH indicatingdownlink allocation or an uplink grant. The BWP switching for a certainserving cell may further be controlled by a BWP inactivity timer,through RRC signaling, or by a MAC entity itself in a case that a randomaccess procedure is initiated. In addition of SpCell (PCell or PSCell)or activation of SCell, one BWP is first active without receiving aPDCCH indicating downlink allocation or an uplink grant. The firstactive DL BWP and a first active UL BWP may be designated by an RRCmessage transmitted from the base station apparatus 3 to the terminalapparatus 1. The active BWP for a certain serving cell is designated byan RRC or a PDCCH transmitted from the base station apparatus 3 to theterminal apparatus 1. Also, the first active DL BWP and the first activeUL BWP may be included in a message 4. In an unpaired spectrum (such asa TDD band), the DL BWP and the UL BWP are paired, and the BWP switchingis common to UL and DL. The MAC entity of the terminal apparatus 1applies normal processing to an active BWP for each activated servingcell for which the BWP is configured. The normal processing includestransmission of the UL-SCH, transmission of the RACH, monitoring of thePDCCH, transmission of the PUCCH, transmission of the SRS, and receptionof the DL-SCH. The MAC entity of the terminal apparatus 1 does nottransmit the UL-SCH, does not transmit the RACH, does not monitor thePDCCH, does not transmit the PUCCH, does not transmit the SRS, and doesnot receive the DL-SCH in an inactive BWP for each activated servingcell for which the BWP is configured. In a case that a certain servingcell is inactivated, the active BWP may not be present (the active BWPmay be deactivated, for example).

RRC Operation

A BWP information element (IE) included in an RRC message (broadcastedsystem information and information transmitted by a dedicated RRCmessage) is used to configure a BWP. The RRC message transmitted fromthe base station apparatus 3 is received by the terminal apparatus 1.For each serving cell, a network (such as the base station apparatus 3)configures, for the terminal apparatus 1, at least an initial BWPincluding at least a downlink BWP and one (in a case that the servingcell is configured in the uplink or the like) or two (in a case that asupplementary uplink is used or the like) uplink BWPs. Further, thenetwork may configure, for a certain serving cell, an additional uplinkBWP or downlink BWP. The BWP configuration is categorized into uplinkparameters and downlink parameters. Also, the BWP configuration iscategorized into common parameters and dedicated parameters. The commonparameters (such as a BWP uplink common IE and a BWP downlink common IE)are unique to each cell. The common parameters of an initial BWP of aprimary cell are provided by system information as well. The networkprovides the common parameters to all the other serving cells withdedicated signals. The BWP is identified by a BWP ID. The initial BWPhas a BWP ID of 0. The BWP IDs of the other BWP are values from 1 to 4.

The initial DL BWP may be defined by a PRB location for a controlresource set (CORESET) for a type 0 PDCCH common search space, thenumber of continuous PRBs, a subcarrier spacing, and a cyclic prefix. Inother words, the initial DL BWP may be configured by pdcch-ConfigSIB1included in MIB or PDCCH-ConfigCommon included inServingCellConfigCommon. The information element ServingCellConfigCommonis used to configure cell-specific parameters of a serving cell for theterminal apparatus 1. In this case, the size of the initial DL BWP isN^(size) _(BWP, 0). N^(size) _(BWP, 0) is a number of resource blocksindicating a bandwidth of the initial DL BWP. Here, the initial DL BWPis an initial DL BWP with the size N^(size) _(BWP, 0).

Also, the initial DL BWP may be provided to the terminal apparatus 1 bysystemInformationBlockType1 (SIB1) or ServingCellConfigCommon (forexample, ServingCellConfigCommonSIB). The information elementServingCellConfigCommonSIB is used to configure cell-specific parametersof the serving cell for the terminal apparatus 1 in the SIB1. In thiscase, the size of the initial DL BWP is N^(size) _(BWP, 1). N^(size)_(BWP, 1) may be equal to N^(size) _(BWP, 0). N^(size) _(BWP, 1) may bedifferent from N^(size) _(BWP, 0). Here, the initial DL BWP is aninitial DL BWP with the size of N^(size) _(BWP, 1).

The initial UL BWP may be provided to the terminal apparatus 1 bysystemInformationBlockType1 (SIB1) or initialUplinkBWP. The informationelement initialUplinkBWP is used to configure the initial UL BWP.

In the present embodiment, the initial DL BWP may be the initial DL BWPwith N^(size) _(BWP, 0) or may be the initial DL BWP with N^(size)_(BWP, 1).

One primary cell and up to fifteen secondary cells may be configured forthe terminal apparatus 1.

FIG. 14 is a flow diagram illustrating an example of a random accessprocedure of the MAC entity according to the present embodiment.

Random Access Procedure Initialization (S1001)

In FIG. 14, S1001 is a procedure regarding random access procedureinitialization. In S1001, the random access procedure is initiated by aPDCCH order, a notification of a beam failure from the MAC entity itselfor a lower layer, the RRC or the like. The random access procedure inthe SCell is initiated only by the PDCCH order includingra-PreambleIndex that is not set in 0b000000.

In S1001, the terminal apparatus 1 receives random access configurationinformation via a higher layer before the random access procedure isinitiated. The random access configuration information may include thefollowing information or one or a plurality of elements of informationfor determining/configuration the following information.

-   -   prach-ConfigIndex: a set of one or a plurality of time/frequency        resources that are available for transmitting a random access        preamble (also referred to as a random access channel occasion,        a PRACH occasion, or a RACH occasion)    -   preambleReceivedTargetPower: initial power of the preamble (this        may be a target reception power)    -   rsrp-ThresholdSSB: a threshold value of a reference signal        reception power (RSRP) for selecting an SS/PBCH block (this may        be an associated random access preamble and/or a PRACH occasion)    -   rsrp-ThresholdCSI-RS: a threshold value of a reference signal        reception power (RSRP) for selecting CSI-RS (this may be an        associated random access preamble and/or a PRACH occasion)    -   rsrp-ThresholdSSB-SUL: a threshold value of a reference signal        reception power (RSRP) for selection between a Normal Uplink        (NUL) carrier and a Supplementary Uplink (SUL) carrier    -   powerControlOffset: a power offset between rsrp-ThresholdSSB and        rsrp-ThresholdCSI-RS in a case that the random access procedure        is initiated for beam failure recovery    -   powerRampingStep: power ramping step (power ramping factor) This        indicates a step of a transmission power ramped up based on a        preamble transmission counter PREAMBLE_TRANSMISSION_COUNTER.    -   ra-PreambleIndex: one or a plurality of random access preamble        that are available or one or a plurality of random access        preambles that are available in the plurality of random access        preamble groups    -   ra-ssb-OccasionMaskIndex: information for determining the PRACH        occasion allocated to the SS/PBCH block with which the MAC        entity transmits the random access preamble    -   ra-OccasionList: information for determining the PRACH occasion        allocated to the CSI-RS with which the MAC entity may transmit        the random access preamble    -   preamTransMax: the maximum number of times the preamble is        transmitted    -   ssb-perRACH-OccasionAndCB-PreamblesPerSSB (SpCell only):        parameters indicating the number of SS/PBCH blocks mapped in        each PRACH occasion and the number of random access preambles        mapped in each SS/PBCH block    -   ra-ResponseWindow: a time window for monitoring a random access        response (SpCell only)    -   ra-ContentionResolutionTimer: collision resolution (contention        resolution) timer    -   numberOfRA-PreamblesGroupA: the number of random access        preambles in a random access preamble group A for each SS/PBCH        block    -   PREAMBLE_TRANSMISSION_COUNTER: a preamble transmission counter    -   DELTA_PREAMBLE: a power offset value based on a random access        preamble format    -   PREAMBLE_POWER_RAMPING_COUNTER: a preamble power ramping counter    -   PREAMBLE_RECEIVED_TARGET_POWER: an initial random access        preamble power; This indicates an initial transmission power for        random access preamble transmission    -   PREAMBLE_BACKOFF: this is used to adjust a timing of the random        access preamble transmission

In a case that the random access procedure is initiated for a certainserving cell, the MAC entity clears an Msg3 buffer, sets a statevariable PREAMBLE_TRANSMISSION_COUNTER to 1, sets a state variablePREAMBLE_POWER_RAMPING_COUNTER to 1, and sets a state variablePREAMBLE_BACKOFF to 0 ms. In a case that a carrier to be used for therandom access procedure is explicitly notified, the MAC entity selectsthe carrier designated by the notification to perform the random accessprocedure and sets a state variable PCMAX to a maximum transmissionpower value of the carrier designated by the notification. In a casethat the carrier to be used for the random access procedure is notexplicitly notified, an SUL carrier is configured for the serving cell,and a downlink pathloss reference RSRP is smaller thanrsrp-ThresholdSSB-SUL, the MAC entity selects the SUL carrier to performthe random access procedure and sets the state variable PCMAX to themaximum transmission power value of the SUL carrier. Otherwise, the MACentity selects a NUL carrier to perform the random access procedure andsets the state variable PCMAX to the maximum transmission power value ofthe NUL carrier.

Random Access Procedure Initialization (S1002)

S1002 is a random access resource selection (random access resourceselection). Hereinafter, a random access resource (includingtime/frequency resources and/or a preamble index) selection procedure inthe MAC layer of the terminal apparatus 1 will be described.

The terminal apparatus 1 sets a value for a preamble index (which may bereferred to as PREAMBLE_INDEX) of a random access preamble to betransmitted in the following procedure.

In a case that (1) the random access procedure is initiated in responseto a notification of a beam failure from the lower layer, (2) a randomaccess resource (which may be a PRACH occasion) for anon-contention-based random access for a beam failure recovery requestassociated with SS/PBCH blocks (which will also be referred to as SSBs)or the CSI-RS has been provided with an RRC parameter, and (3) the RSRPof one or more SS/PBCH blocks or the CSI-RS exceeds a predeterminedthreshold value, the terminal apparatus 1 (MAC entity) selects theSS/PBCH blocks or the CSI-RS with RSRP exceeding the predeterminedthreshold value. In a case that there is no ra-PreambleIndex, for whichthe CSI-RS has been selected, and which is associated with the selectedCSI-RS, the MAC entity may set ra-PreambleIndex associated with theselected SS/PBCH blocks to the preamble index (PREAMBLE_INDEX).Otherwise, the MAC entity sets ra-PreambleIndex associated with theselected SS/PBCH blocks or the CSI-RS to the preamble index.

In a case that (1) ra-PreambleIndex is provided with the PDCCH or theRRC, (2) the value of ra-PreambleIndex is not a value indicating acontention-based random access procedure (0b000000, for example), and(3) the SS/PBCH blocks or the CSI-RS and the random access resource forthe non-contention-based random access are not associated with the RRC,the terminal apparatus 1 sets signaled ra-PreambleIndex to the preambleindex. 0bxxxxxx means a bit sequence allocated in a 6-bit informationfield.

In a case that (1) a random access resource for the non-contention-basedrandom access associated with the SS/PBCH blocks have been provided fromthe RRC, and (2) one or more SS/PBCH blocks with RSRP exceeding thepredetermined threshold value are available from among the associatedSS/PBCH blocks, the terminal apparatus 1 selects one of the SS/PBCHblocks with RSRP exceeding the predetermined threshold value and setsra-PreambleIndex associated with the selected SS/PBCH block to thepreamble index.

In a case that (1) the CSI-RS and the random access resource for thenon-contention-based random access have been associated with the RRC,and (2) one or more CSI-RSs with RSRP exceeding the predeterminedthreshold value is available from among the associated CSI-RSs, theterminal apparatus 1 selects one of the CSI-RSs with RSRP exceeding thepredetermined threshold value and sets ra-PreambleIndex associated withthe selected CSI-RS to the preamble index.

The terminal apparatus 1 performs a contention-based random accessprocedure in a case that any of the aforementioned conditions is met. Inthe contention-based random access procedure, the terminal apparatus 1selects SS/PBCH blocks that have SS/PBCH block RSRP exceeding aconfigured threshold value and performs selection of a preamble group.In a case that a relationship between the SS/PBCH blocks and randomaccess preambles has been configured, the terminal apparatus 1 randomlyselects ra-PreambleIndex from one or a plurality of random accesspreambles associated with the selected SS/PBCH blocks and the selectedpreamble group and sets selected ra-PreambleIndex to the preamble index.

In a case that the MAC entity selects one SS/PBCH block and associationbetween PRACH occasions and the SS/PBCH block has been configured, theMAC entity may determine a next available PRACH occasion from among thePRACH occasions associated with the selected SS/PBCH block. However, ina case that the terminal apparatus 1 selects one CSI-RS and associationbetween PRACH occasions and the CSI-RS has been configured, the terminalapparatus 1 may determine a next available PRACH occasion from among thePRACH occasions associated with the selected CSI-RS.

The available PRACH occasion may be specified based on mask indexinformation, SSB index information, resource configuration configuredwith the RRC parameter, and/or a selected reference signal (SS/PBCHblock or CSI-RS). The resource configuration configured with the RRCparameter includes resource configuration for each SS/PBCH block and/orresource configuration for each CSI-RS.

The base station apparatus 3 may transmit, to the terminal apparatus 1,the resource configuration for each SS/PBCH block and/or the resourceconfiguration for each CSI-RS in an RRC message. The terminal apparatus1 receives, from the base station apparatus 3, the resourceconfiguration for each SS/PBCH block and/or the resource configurationfor each CSI-RS in the RRC message. The base station apparatus 3 maytransmit, to the terminal apparatus 1, mask index information and/or SSBindex information. The terminal apparatus 1 acquires, from the basestation apparatus 3, the mask index information and/or the SSB indexinformation. The terminal apparatus 1 may select a reference signal(SS/PBCH block or CSI-RS) based on certain conditions. The terminalapparatus 1 may specify the next available PRACH occasion based on themask index information, the SSB index information, the resourceconfiguration configured with the RRC parameter, and the selectedreference signal (SS/PBCH block or CSI-RS). The MAC entity of theterminal apparatus 1 may indicate, to a physical layer, to transmit therandom access preamble using the selected PRACH occasion.

The mask index information is information indicating the index of thePRACH occasion that is available for transmitting the random accesspreamble. The mask index information may be information indicating somePRACH occasions in a group of one or a plurality of PRACH occasionsdefined by prach-ConfigurationIndex. The mask index information may beinformation indicating some PRACH occasions in a group of PRACHoccasions to which specific SSB indexes specified by the SSB indexinformation have been mapped.

The SSB index information is information indicating an SSB indexcorresponding to any one of one or a plurality of SS/PBCH blockstransmitted by the base station apparatus 3. The terminal apparatus 1that has received a message 0 specifies the group of PRACH occasions towhich the SSB indexes indicated by the SSB index information have beenmapped. The SSB index mapped to each PRACH occasion is determined by aPRACH configuration index, higher layer parameter SB-perRACH-Occasion,and a higher layer parameter cb-preamblePerSSB.

Random Access Preamble Transmission (S1003)

S1003 is a procedure regarding random access preamble transmission. In acase that (1) the state variable PREAMBLE_TRANSMISSION_COUNTER isgreater than 1, (2) a notification of a stopped power ramp counter hasnot been received from the higher layer, and (3) the selected SS/PBCHblock has not been changed, the MAC entity increments the state variablePREAMBLE_POWER_RAMPING_COUNTER by one for each random access preamble.

Next, the MAC entity selects a value of DELTA_PREAMBLE and sets thestate variable PREAMBLE_RECEIVED_TARGET_POWER to a predetermined value.The predetermined value is calculated bypreambleReceivedTargetPower+DELTA_PREAMBLE+(PREAMBLE_POWER_RAMPING_COUNTER−1)*powerRampingStep.

Next, in a case other than the non-contention-based random accesspreamble, the MAC entity calculates RA-RNTI associated with the PRACHoccasion in which the random access preamble is transmitted for a beamfailure recovery request. This Ra-RNTI is calculated byRA-RNTI=1+s_id+14×t_id+14×80×f_id+14×80×8×ul_carrier_id. Here, s_id isan index of the first OFDM symbol in the transmitted PRACH and is avalue of 0 to 13. t_id is an index of the first slot of the PRACH in thesystem frame and is a value of 0 to 79. f_id is an index of the PRACH inthe frequency domain and is a value of 0 to 7. ul_carrier_id is anuplink carrier used for Msg1 transmission. ul_carrier_id for the NULcarrier is 0 while ul_carrier_id for the SUL carrier is 1.

The MAC entity indicates, to the physical layer, to transmit the randomaccess preamble using the selected PRACH.

Random Access Response Reception (S1004)

S1004 is a procedure regarding random access response reception. Oncethe random access preamble is transmitted, the MAC entity performs thefollowing operations regardless of possible occurrence of a measurementgap. Here, the random access response may be a MAC PDU for a randomaccess response.

The MAC PDU (MAC PDU of the random access response) includes one or aplurality of MAC subPDUs and possible padding. Each MAC subPDU includesany of the following elements.

-   -   MAC subheader including only Backoff Indicator    -   MAC subheader indicating only RAPID    -   MAC subheader and MAC payload for Random Access Response (MAC        RAR) indicating RAPID

MAC subPDU including only Backoff Indicator is allocated at the head ofMAC PDU. Padding is allocated at the end of MAC PDU. MAC subPDUincluding only RAPID and MAC subPDU including RAPID and MAC RAR can beallocated anywhere between MAC subPDU including only Backoff Indicatorand the padding.

MAC RAR has a fixed size and includes reserved bits set to 0,transmission timing adjustment information (Timing Advance (TA)command), a UL grant (RAR UL grant) and TEMPORARY_C-RNTI. Hereinafter,the RAR message may be MAC RAR. The RAR message may be a random accessresponse.

In S1004, in a case that the MAC entity transmits a non-contention-basedrandom access preamble for a beam failure recovery request, then the MACentity starts a random access response window (ra-ResponseWindow) in thefirst PDCCH occasion after the end of the random access preambletransmission. Then, the MAC entity monitors the PDCCH of the SpCellidentified by the C-RNTI for a response to the beam failure recoveryrequest in a case that the random access response window is running.Here, a period (window size) of the random access response window isprovided by ra-ResponseWindow included in a higher layer parameterBeamFailureRecoveryConfig. Otherwise, the MAC entity starts the randomaccess response window (ra-ResponseWindow) in the first PDCCH occasionafter the end of the random access preamble transmission. Here, theperiod (window size) of the random access response window is provided byra-ResponseWindow included in the higher layer parameterRACH-ConfigCommon. Also, the MAC entity monitors the PDCCH of the SpCellidentified by RA-RNTI for a random access response in a case that therandom access response window is running. Here, the information elementBeamFailureRecoveryConfig is used to configure a RACH resource and acandidate beam for a beam failure recovery for the terminal apparatus 1in a case that a beam failure has been detected. The information elementRACH-ConfigCommon is used to designate a cell-specific random accessparameter.

In a case that (1) a reception notification of the PDCCH transmissionhas been received from the lower layer, (2) the PDCCH transmission hasbeen scrambled with C-RNTI, and (3) the MAC entity has transmitted anon-contention-based random access preamble for a beam failure recoveryrequest, the MAC entity may regard the random access procedure as havingsuccessfully been completed.

Next, in a case that (1) downlink assignment has been received by thePDCCH of RA-RNTI, and (2) the received transport block has successfullybeen decoded, the MAC entity performs the following operations.

In a case that the random access response includes MAC subPDU includingBackoff Indicator, the MAC entity configures PREAMBLE_BACKOFF to a valueof a BI field included in MAC subPDU. Otherwise, the MAC entity setsPREAMBLE_BACKOFF to 0 ms.

In a case that the random access response includes MAC subPDU includinga random access preamble identifier corresponding to transmittedPREAMBLE_INDEX, the MAC entity may regard the random access response ashaving successfully been received.

In a case that (1) the reception of the random access response isregarded as having successfully been received, and (2) the random accessresponse includes MAC subPDU including only RAPID, the MAC entityregards the random access procedure as having successfully beencompleted and indicates, for the higher layer, reception of a positiveresponse (acknowledgement) to a system information (SI) request. Here,in a case that the condition (2) is not met, the MAC entity applies thefollowing operation A to the serving cell in which the random accesspreamble is to be transmitted.

Start of Operation A

The MAC entity processes the received transmission timing adjustmentinformation (Timing Advance Command) and indicates, for the lower layer,the amounts of preambleReceivedTargetPower and power ramping applied tothe latest random access preamble transmission. Here, the transmissiontiming adjustment information is used to adjust a transmission timingdeviation between the terminal apparatus 1 and the base stationapparatus 3 from the received random access preamble.

In a case that the serving cell for the random access procedure is theSCell only for the SRS, the MAC entity may ignore the received UL grant.Otherwise, the MAC entity processes the value of the received UL grantand indicates the processed value for the lower layer.

In a case that the random access preamble is not selected from the rangeof contention-based random access preambles by the MAC entity, the MACentity may regard the random access procedure as having successfullybeen completed.

End of Operation A

In a case that the random access preamble is selected from the range ofthe contention-based random access preambles by the MAC entity, the MACentity sets TEMPORARY_C-RNTI to a value of Temporary C-RNTI fieldincluded in the received random access response. Subsequently, in a casethat the random access response has successfully been received for thefirst time in the random access procedure, and in a case that notransmission has been performed for common control channel (CCCH)logical channel, the MAC entity notifies a inclusion of C-RNTI MAC CE inthe next uplink transmission to a predetermined entity (Multiplexing andassembly entity), acquires MAC PDU for transmission from thepredetermined entity (Multiplexing and assembly entity), and stores theacquired MAC PDU in the Msg3 buffer. In a case that transmission isperformed for the CCCH logical channel, the MAC entity acquires the MACPDU for transmission from the predetermined entity (Multiplexing andassembly entity) and stores the acquired MAC PDU in the Msg3 buffer.

In a case that at least one of the following conditions (3) and (4) ismet, the MAC entity regards the random access response as not havingsuccessfully been received and increments the preamble transmissioncounter (PREAMBLE_TRANSMISSION_COUNTER) by one. In a case that the valueof the preamble transmission counter reaches a predetermined value (themaximum number of times the preamble is transmitted+1), and the randomaccess preamble is transmitted by SpCell, the MAC entity indicates arandom access problem to the higher layer. Then, in a case that therandom access procedure is initiated for an SI request, the MAC entityregards the random access procedure as not having successfully beencompleted.

In a case that the value of the preamble transmission counter reachesthe predetermined value (the maximum number of times the preamble istransmitted+1) and the random access preamble is transmitted by theSCell, the MAC entity regards the random access procedure as not havingsuccessfully been completed.

The condition (3) is that the period of the random access responsewindow configured by RACH-ConfigCommon has been expired and a randomaccess response including a random access preamble identifier thatcoincides with the transmitted preamble index has not been received. Thecondition (4) is that the period of the random access response windowconfigured by BeamFailureRecoveryConfig has been expired and the PDCCHscrambled with C-RNTI has not been received.

In a case that the random access procedure has not been completed, andin a case that the random access preamble has been selected from therange of the contention-based random access preambles by the MAC itselfin the random access procedure, the MAC entity selects a random backofftime between 0 and PREAMBLE_BACKOFF, delays the next random accesspreamble transmission with the selected backoff time, and then executesS1002. In the case in which the random access procedure has not beencompleted, and in a case that the random access preamble has not beenselected from the range of the contention-based random access preamblesby the MAC itself in the random access procedure, the MAC entityexecutes S1002.

In a case that the random access response including the random accesspreamble identifier that coincides with the transmitted preamble indexhas successfully been received, the MAC entity may stop the randomaccess response window.

The terminal apparatus 1 transmits the message 3 in the PUSCH based onthe UL grant.

Collision Resolution (S1005)

S1005 is a procedure for collision resolution (contention resolution).

Once Msg3 is transmitted, the MAC entity starts the collision resolutiontimer and restarts the collision resolution timer in a case that eachHARQ is retransmitted. The MAC entity monitors the PDCCH in a case thatthe collision resolution timer is running, regardless of possibleoccurrence of a measurement gap.

In a case that a reception notification of PDCCH is received from thelower layer and C-RNTI MAC CE is included in Msg3, and in a case that atleast one of the following conditions (5) to (7) is satisfied, the MACentity regards the contention resolution as being successfullyperformed, stops the collision resolution timer, discardsTEMPORARY_C-RNTI, and regards the random access procedure as havingsuccessfully been completed.

The condition (5) is that the random access procedure is initiated by aMAC sublayer or an RRC sublayer, PDCCH transmission is scrambled withC-RNTI, and the PDCCH transmission includes an uplink grant for initialtransmission. The condition (6) is that the random access procedure isinitiated by a PDCCH order, and the PDCCH transmission is scrambled withC-RNTI. The condition (7) is that the random access procedure isinitiated for beam failure recovery, and the PDCCH transmission isscrambled with C-RNTI.

In a case that CCCH SDU (UE contention resolution identity) is includedin Msg3, and the PDCCH transmission is scrambled with TEMPORARY_C-RNTI,and in a case that the MAC PDU is successfully be decoded, then the MACentity stops the collision resolution timer. Subsequently, in a casethat the successfully decoded MAC PDU includes UE collision resolutionidentity (UE contention resolution identity) MAC CE, and the UEcollision resolution identity in the MAC CE is matched with the CCCH SDUtransmitted in Msg3, the MAC entity regards the collision resolution asbeing successfully performed and ends disassembly and demultiplexing ofthe MAC PDU. Then, in a case that the random access procedure isinitiated by an SI request, the MAC entity indicates reception of apositive response to the SI request for the higher layer. In a case thatthe random access procedure is not initiated by the SI request, the MACentity sets the C-RNTI to the value of TEMPORARY_C-RNTI. Subsequently,the MAC entity discards TEMPORARY_C-RNTI and regards the random accessprocedure as being successfully completed.

In a case that the UE collision resolution identity in the MAC CE is notmatched with the CCCH SDU transmitted in Msg3, the MAC entity discardsTEMPORARY_C-RNTI, regards the collision resolution as not beingsuccessfully performed, and discards the MAC PDU that has successfullybeen decoded.

In a case that the collision resolution timer is expired, the MAC entitydiscards TEMPORARY_C-RNTI and regards the contention resolution as notbeing successfully performed. In a case that the contention resolutionis regarded as not being successfully performed, the MAC entity flush aHARQ buffer used to transmit the MAC PDU in the Msg3 buffer, andincrements a preamble transmission counter(PREAMBLE_TRANSMISSION_COUNTER) by one. In a case that the value of thepreamble transmission counter reaches a predetermined value (the maximumnumber of times the preamble is transmitted+1), then the MAC entityindicates a random access problem for the higher layer. Then, in a casethat the random access procedure is initiated for an SI request, the MACentity regards the random access procedure as not having successfullybeen completed.

In a case that the random access procedure has not been completed, theMAC entity selects a random backoff time between 0 and PREAMBLE_BACKOFF,delays the next random access preamble transmission with the selectedbackoff time, and executes S1002.

In a case that the random access procedure is completed, then the MACentity discards the non-contention-based random access resourceexplicitly signaled for the non-contention-based random access procedureother than the non-contention-based random access procedure for a beamfailure recovery request and flushes the HARQ buffer used to transmitthe MAC PDU in the Msg3 buffer.

Hereinafter, the control resource set (CORESET) according to the presentembodiment will be described.

The control resource set (CORESET) is time and frequency resources forsearching for downlink control information. CORESET configurationinformation includes CORESET identifiers (ControlResourceSetId,CORESET-ID) and information specifying CORESET frequency resource. Theinformation element ControlResourceSetId (CORESET identifier) is used tospecify a control resource set in a certain serving cell. The CORESETidentifier is used among BWPs in a certain serving cell. The CORESETidentifier is unique among the BWPs in the serving cell. The number ofCORESETS in each BWP is limited to three including an initial CORESET.The value of the CORESET identifier in a certain serving cell is a valueof 0 to 11.

The control resource set specified by the identifier 0(ControlResourceSetId 0) of the CORESET will be referred to asCORESET#0. CORESET#0 may be configured by pdcch-ConfigSIB1 included inMIB or PDCCH-ConfigCommon included in ServingCellConfigCommon. In otherwords, the configuration information of CORESET#0 may be pdcc-ConfigSIB1included in MIB or PDCCH-ConfigCommon included inServingCellConfigCommon. The configuration information of CORESET#0 maybe configured by controlResourceSetZero included in PDCCH-ConfigSIB1 orPDCCH-ConfigCommon. In other words, an information elementcontrolResourceSetZero is used to indicate CORESET#0 (common CORESET) ofthe initial DL BWP. The CORESET indicated by pdcch-ConfigSIB1 isCORESET#0. The information element pdcch-ConfigSIB1 in the MIB or thededicated configuration is used to configure the initial DL BWP.Although information that explicitly specifies a CORESET identifier anda frequency resource (for example, the number of continuous resourceblocks) and a time resource (the number of continuous symbols) of theCORESET is not included in the CORESET configuration informationpdcch-ConfigSIB1 for CORESET#0, the frequency resource (for example, thenumber of continuous resource blocks) and the time resource (the numberof continuous symbols) of the CORESET for CORESET#0 can be explicitlyspecified by the information included in pdcch-ConfigSIB1. Theinformation element PDCCH-ConfigCommon is used to configure acell-specific PDCCH parameter provided by the SIB. Also,PDCCH-ConfigCommon may be provided at the time of handover and PSCelland/or SCell addition. The configuration information of CORESET#0 isincluded in the configuration of the initial BWP. In other words, theconfiguration information of CORESET#0 may not be included in theconfiguration of BWPs other than the initial BWP. controlResourceSetZerocorresponds to 4 bits (for example, MSB 4 bits; 4 bits of the highestbits) in pdcch-ConfigSIB1. CORESET#0 is a control resource set for thetype 0 PDCCH common search space.

Configuration information of an additional common control resource set(CORESET) may be configured by commonControlResourceSet included inPDCCH-ConfigCommon. The configuration information of the additionalcommon CORESET may be used to designate the additional common CORESETused for the random access procedure. The configuration information ofthe additional common CORESET may be included in configuration of eachBWP. The identifier of the CORESET indicated by commonControlResourceSetis a value other than 0.

The common CORESET may be a CORESET (for example, the additional commonCORESET) used for the random access procedure. Also, a CORESETconfigured by CORESET#0 and/or the configuration information of theadditional common CORESET may be included in the common CORESET in thepresent embodiment. In other words, the common CORESET may includeCORESET#0 and/or the additional common CORESET. CORESET#0 may bereferred to as common CORESET#0. The configuration information of thecommon CORESET may be referred to (acquired) by the terminal apparatus 1and for the BWPs other than the BWP for which the common CORESET hasbeen configured.

Configuration information of one or a plurality of CORESETs may beconfigured by PDCCH-Config. The information element PDCCH-Config is usedto configure UE-specific PDCCH parameters (for example, a CORESET, asearch space, and the like) for a certain BWP. The PDCCH-Config may beincluded in the configuration of each BWP.

In other words, the configuration information of the common CORESETindicated by the MIB is pdcch-ConfigSIB1, the configuration informationof the common CORESET indicated by PDCCH-ConfigCommon iscontrolResourceSetZero, and the configuration information of the commonCORESET (additional common CORESET) indicated by PDCCH-ConfigCommon iscommonControlResourceSet. In addition, the configuration information ofone or a plurality of CORESETs (UE specifically configured ControlResource Sets, UE-specific CORESET) indicated by PDCCH-Config iscontrolResourceSetToAddModList.

The search space is defined to search for PDCCH candidates.searchSpaceType included in the configuration information of the searchspace indicates which of a Common Search Space (CSS) and a UE-specificSearch Space (USS) the search space is. The UE-specific search space isderived at least from the value of C-RNTI set by the terminal apparatus1. In other words, the UE-specific search space is individually derivedfrom each terminal apparatus 1. The common search space is a searchspace common to a plurality of terminal apparatuses 1 and includes aControl Channel Element (CCE) of an index defined in advance. The CCEincludes a plurality of resource elements. Information of the DCI formatmonitored in the search space is included in the configurationinformation of the search space.

An identifier of the CORESET specified by the configuration informationof the CORESET is included in the configuration information of thesearch space. The CORESET specified by the identifier of the CORESETincluded in the configuration information of the search space isassociated with the search space. In other words, the CORESET associatedwith the search space is the CORESET specified by the identifier of theCORESET included in the search space. The DCI format indicate by theconfiguration information of the search space is monitored by theassociated CORESET. Each search space is associated with a singleCORESET. For example, the configuration information of the search spacefor the random access procedure may be configured by ra-SearchSpace. Inother words, the DCI format to which the CRC scrambled with RA-RNTI orTC-RNTI is added is monitored by the CORESET associated withra-SearchSpace.

As described above, the configuration information of CORESET#0 isincluded in the configuration of the initial DL BWP. The configurationinformation of CORESET#0 may not be included in the configuration of theBWPs (additional BWPs) other than the initial DLBWP. In a case that theBWPs (additional BWPs) other than the initial DL BWP refers to (oracquires) the configuration information of CORESET#0, it may benecessary to satisfy at least that CORESET#0 and the SS block beincluded in the additional BWPs in the frequency domain and that thesame subcarrier spacing is used. In other words, it may be necessary tosatisfy at least that the bandwidth of the initial DL BWP and the SSblock are included in the additional BWPs in the frequency domain andthat the same subcarrier spacing is used in a case that the BWPs(additional BWPs) other than the initial BWP refers to (or acquires) theconfiguration information of CORESET#0. At this time, the search space(for example, ra-SearchSpace) configured for the additional BWPs canrefer to (or acquire) the configuration information of CORESET#0 byindicating the identifier 0 of CORESET#0. Also, in a case that any ofthe conditions that the bandwidth of the initial DL BWP is included inan additional DL BWP in the frequency domain, that the SS block isincluded in the additional DL BWP, and that the same subcarrier spacingis used is not satisfied, the terminal apparatus 1 may not expect thatthe additional DL BWP refers to the configuration information ofCORESET#0. In other words, the base station apparatus 3 may notconfigure that the additional DL BWP refers to the configurationinformation of CORESET#0 for the terminal apparatus 1 in this case.Here, the initial DL BWP may be an initial DL BWP with the size N^(size)_(BWP, 0).

In a case that a certain (additional) DL BWP refers to (or acquires) theconfiguration information of the CORESET of another BWP, it may benecessary to satisfy at least that in the frequency domain the CORESET(or the bandwidth of the BWP) and/or the SS block included in(associated with) the BWP is included in the additional BWP and the samesubcarrier spacing is used. In other words, in a case that any of theconditions that the CORESET (or the bandwidth of the BWP) is included inthe additional DL BWP in the frequency domain, that the SS blockincluded in (associated with) the BWP is included in the additional DLBWP, and that the same subcarrier spacing is used is not satisfied, theterminal apparatus 1 may not expect that the additional DL BWP refers tothe configuration information of the CORESET configured for the BWP.

The terminal apparatus 1 monitors a set of PDCCH candidates in one or aplurality of CORESETs allocated in each active serving cell configuredto monitor the PDCCH. The set of PDCCH candidates corresponds to one ora plurality of search space sets. The monitoring means that each PDCCHcandidate is decoded in accordance with one or a plurality of DCIformats to be monitored. The set of PDCCH candidates monitored by theterminal apparatus 1 is defined by PDCCH search space sets. One searchspace set is a common search space set or a UE-specific search spaceset. In the above description, the search space set has been referred toas the search space, the common search space set has been referred to asthe common search space, and the UE-specific search space set has beenreferred to as the UE-specific search space set. The terminal apparatus1 monitors the PDCCH candidates with the following one or a plurality ofsearch space sets.

-   -   Type0-PDCCH common search space set: this search space set is        configured by searchSpaceZero indicated by the MIB or        searchSpaceSIB1 indicated by PDCCH-ConfigCommon that is a        parameter of the higher layer. The search space is for the        monitoring of the DCI format of the CRC scrambled with the        SI-RNRI in the primary cell.    -   Type0A-PDCCH common search space set: the search space set is        configured by searchSpace-OSI indicated by PDCCH-ConfigCommon        that is a parameter of the higher layer. The search space is for        the monitoring of the DCI format of the CRC scrambled with the        SI-RNRI in the primary cell.    -   Type1-PDCCH common search space set: this search space set is        configured by a search space (ra-SearchSpace) for the random        access procedure indicated by the PDCCH-ConfigCommon that is a        parameter of the higher layer. The search space is for the        monitoring of the DCI format of the CRC scrambled with the        RA-RNRI or TC-RNTI in the primary cell. The Type1-PDCCH common        search space set is a search space set for the random access        procedure.    -   Type2-PDCCH common search space set: this search space set is        configured by a search space (pagingSearchSpace) for paging        procedure indicated by PDCCH-ConfigCommon that is a parameter of        the higher layer. This search space is for the monitoring of the        DCI format of the CRC scrambled with the P-RNTI in the primary        cell.    -   Type3-PDCCH common search space set: this search space set is        configured by a SearchSpace of a common search space type        indicated by PDCCH-Config that is a parameter of the higher        layer. The search space is for the monitoring of the DCI format        of the CRC scrambled with the INT-RNTI, the SFI-RNTI, the        TPC-PUSCH-RNTI, the TPC-PUCCH-RNTI, or the TPC-SRS-RNTI. For the        primary cell, the search space is for the monitoring of the DCI        format of the CRC scrambled with the C-RNTI or the CS-RNTI(s).    -   UE-specific search space set: this search space set is        configured by SearchSpace of a UE-specific search space type        indicated by PDCCH-Config that is a parameter of the higher        layer. The search space is for the monitoring of the DCI format        of the CRC scrambled with the C-RNTI or the CS-RNTI(s).

In a case that one or a plurality of search space sets are provided tothe terminal apparatus 1 by the corresponding higher layer parameter(searchSpaceZero, searchSpaceSIB1, searchSpaceOtherSystemInformation,pagingSearchSpace, ra-SearchSpace, or the like), and the C-RNTI or theCS-RNTI is provided by the terminal apparatus 1, the terminal apparatus1 may monitor the PDCCH candidates for the DCI format 0_0 and the DCIformat 1_0 having the C-RNTI or the CS-RNTI with the one or theplurality of search space sets.

The configuration information of BWPs is categorized into configurationinformation of the DL BWP and configuration information of the UL BWP.The configuration information of BWPs includes information elementsbwp-Id (BWP identifiers). The BWP identifier included in theconfiguration information of the DL BWP is used to specify (refer to)the DL BWP in a certain serving cell. The BWP identifier included in theconfiguration information of the UL BWP is used to specify (refer to)the UL BWP in a certain serving cell. The BWP identifier is applied toeach of the DL BWP and the UL BWP. For example, the BWP identifiercorresponding to the DL BWP may be referred to as a DL BWP index. TheBWP identifier corresponding to the UL BWP may be referred to as a ULBWP index. The initial DL BWP is referred to by the identifier 0 of theDL BWP. The initial UL BWP is referred to by the identifier 0 of the ULBWP. Each of other DL BWPs and other UL BWPs may be referred to by theBWP identifiers 1 to maxNrofBWPs. In other words, the BWP identifier setto 0 (bwp-Id=0) is associated with the initial BWP and cannot be usedfor other BWPs. maxNrofBWPs is the maximum number of the BWPs perserving cell and is 4. In other words, the values of the other BWPidentifiers are values of 1 to 4. The configuration information of otherhigher layers is associated with specific BWPs using BWP identifiers.The fact that the DL BWP and the UL BWP have the same BWP identifiermeans that the DL BWP and the UL BWP have been paired.

FIG. 7 is a diagram illustrating an example of BWP configurationaccording to the embodiment of the present invention.

For each serving cell, one initial BWP including at least one DL BWP andone UL BWP is configured. Also, an additional BWP (an additional UL BWPand/or an additional DL BWP) may be configured for each serving cell. Amaximum of four additional BWPs may be configured. However, the numberof DL BWPs that becomes active is one, and the number of UL BWPs thatbecomes active is one, in one serving cell.

In FIG. 7, one initial BWP (BWP#0) and two additional BWPs (BWP#1 andBWP#2) are configured for the terminal apparatus 1 in a certain servingcell. 801 is an initial DL BWP (DL BWP#0). 802 is an initial UL BWP (ULBWP#0). 805 is an additional DL BWP (DL BWP#1). 806 is an additional ULBWP (UL BWP#1). 808 is an additional DL BWP (DL BWP#2). 809 is anadditional UL BWP (UL BWP#2). Hereinafter, it is assumed that DL BWP#1has been activated and UL BWP#0 has been activated. In other words, DLBWP#0 and UL BWP#1 are inactive BWPs. DL BWP#2 and UL BWP#2 are inactiveBWPs. In this case, activated DL BWP#1 may be referred to as an activeDL BWP (active DL BWP, currently active DL BWP). Activated initial ULBWP#0 may be referred to as an initial active UL BWP. The terminalapparatus 1 executes downlink reception using active DL BWP#1 andexecutes uplink transmission using initial active UL BWP.

803 is CORESET#0 configured for the initial DL BWP. 804 is theadditional common CORESET configured for the initial DL BWP. 807 is theCORESET configured for the additional BWP#1. 810 is the CORESETconfigured for the additional BWP#2. 807 and 810 may be referred to asUE-specific CORESETs (UE specifically configured Control Resource Sets).As described above, the configuration information of CORESET#0 (803) maybe configured by pdcch-ConfigSIB1 or PDCCH-ConfigCommon. Theconfiguration information of the additional common CORESET (804) may beconfigured by commonControlResourceSet included in PDCCH-ConfigCommon.The configuration information of CORESETs (807 and 810) may beconfigured by controlResourceSetToAddModList included in PDCCH-Config.The value of the CORESET identifier of 803 is provided by 0. The valueof the CORESET identifier of 804 may be provided by 1. The value of theCORESET identifier of 807 may be provided by 3. The value of the CORESETidentifier of 810 may be provided by 6. The value of the CORESETidentifier included in ra-searchspace is set to 1 for DL BWP#0, and thevalue of the CORESET identifier included in ra-searchspace is set to 6for DL BWP#2.

In FIG. 7, ra-searchspace is configured for each of DL BWP#0, DL BWP#1,and DL BWP#2. As described above, the configuration information of thesearch space for the random access procedure may be configured byra-SearchSpace. In a first example, a CORESET identifier included inra-searchspace configured for a certain DL BWP may be set to a value ofa CORESET identifier specifying configuration information of a CORESETconfigured for the DL BWP or may be set to a value of the CORESETidentifier included in ra-SearchSpace configured for the initial BWP. Inother words, ra-searchspace configured for a certain DL BWP may indicatea CORESET identifier specifying configuration information of a CORESETconfigured for the DL BWP or may indicate a CORESET identifier includedin ra-SearchSpace configured for the initial BWP. In other words, forra-searchspace configured for a certain DL BWP, common and UE-specificCORESET identifiers configured for DL BWPs other than the DL BWP and theinitial DL BWP may not be indicated. In other words, the base stationapparatus 3 may transmit an RRC message such that for ra-searchspaceconfigured for a certain DL BWP, the common and UE-specific CORESETidentifiers configured for DL BWPs other than the DL BWP and the initialDL BWP are not indicated. For example, the value of the CORESETidentifier included in ra-searchspace may be set to 1 or 3 for DL BWP#1.The value of the CORESET identifier included in ra-searchspace is notset to 6 for DL BWP#1. In a case that the value of the CORESETidentifier included in ra-searchspace is set to 1 for DL BWP#1, theterminal apparatus 1 monitors the DCI format included in ra-searchspaceusing active DL BWP#1 based on the configuration information ofCORESET#1 (804) specified by the CORESET identifier 1. In a case thatthe value of the CORESET identifier included in ra-searchspace is set to3 for DL BWP#1, the terminal apparatus 1 monitors the DCI formatincluded in ra-searchspace using active DL BWP#1 based on theconfiguration information of CORESET#3 (807) specified by the CORESETidentifier 3. In other words, ra-searchspace configured for a certain DLBWP may indicate a CORESET identifier specifying the configurationinformation of the common CORESET. For example, the value of the CORESETidentifier included in ra-searchspace may be set to 1 for DL BWP#1. Inother words, in a case that CORESET#1 has been configured for theinitial DL BWP, CORESET#0 cannot be called as ra-searchspace. In a casethat CORESET#1 has not been configured for the initial DL BWP, CORESET#0can be called as ra-searchspace. However, even in a case that CORESET#1has been configured for the initial DL BWP, CORESET#0 can be called asra-searchspace by the DL BW as expansion of the first example.

Also, in a second example, a CORESET identifier included inra-searchspace configured for a certain DL BWP may be set to a value ofa CORESET identifier specifying configuration information of the commonCORESET configured for the DL BWP or may be set to a value of a commonCORESET identifier for a random access procedure configured for anotherBWP. In other words, ra-searchspace configured for a certain DL BWP mayindicate a CORESET identifier specifying the configuration informationof the common CORESET configured for the DL BWP or may indicate thecommon CORESET identifier for the random access procedure configured foranother BWP. For example, the value of the CORESET identifier includedin ra-searchspace may be set to 1, may be set to 3, or may be set to 6for DL BWP#1. In other words, in a case that CORESET#1 has beenconfigured for the initial DL BWP, CORESET#0 cannot be called asra-searchspace of the DL BWP. In a case that CORESET#1 has not beenconfigured for the initial DL BWP, CORESET#0 can be called asra-searchspace of the DL BWP.

In a third example, the CORESET identifier included in ra-searchspaceconfigured for a certain DL BWP may be set to values of all commonCORESET identifiers configured for the terminal apparatus 1. In otherwords, ra-searchspace configured for a certain DL BWP may indicateCORESET identifiers specifying configuration information of all thecommon CORESET configured for the serving cell. For example, the valueof the CORESET identifier included in ra-searchspace may be set to 0, 1,3, or 6 for DL BWP#1.

The value may be set to the value of the CORESET identifier specifyingthe configuration information of CORESET configured for the DL BWP ormay be set to the value of the CORESET identifier configured for anotherBWP. In other words, ra-searchspace configured for a certain DL BWP mayindicate the CORESET identifier specifying the configuration informationof the CORESET configured for the DL BWP or may indicate the identifierof the common CORESET configured for another BWP. For example, the valueof the CORESET identifier included in ra-searchspace may be set to 0,may be set to 1, may be set to 3, or may be set to 6 for DL BWP#1.

A random access procedure according to the present embodiment will bedescribed. The random access procedure is categorized into twoprocedures, namely a Contention-Based (CB) procedure and anon-contention based (non-CB) (which may be referred to as a ContentionFree (CF) procedure. The contention-based random access will also bereferred to as CBRA while the non-contention-based random access willalso be referred to as CFRA.

The random access procedure may have (i) transmission of a random accesspreamble (message 1, Msg1) in the PRACH, (ii) reception of random accessresponse (RAR) message accompanying PDCCH/PDSCH (message 2, Msg2), andif applicable, (iii) transmission of a message 3 PUSCH (Msg3 PUSCH), and(iv) reception of the PDSCH for collision resolution.

The contention-based random access procedure is initiated by a PDCCHorder, a notification of a beam failure from the MAC entity or the lowerlayer, RRC, or the like. In a case that the beam failure notification isprovided from the physical layer of the terminal apparatus 1 to the MACentity of the terminal apparatus 1, and in a case that a certaincondition is met, the MAC entity of the terminal apparatus 1 initiatesthe random access procedure. The procedure in which in a case that thebeam failure notification is provided from the physical layer of theterminal apparatus 1 to the MAC entity of the terminal apparatus 1,whether or not a certain condition is met is determined, and the randomaccess procedure is then initiated may be referred to as a beam failurerecover procedure. The random access procedure is a random accessprocedure for a beam failure recovery request. The random accessprocedure initiated by the MAC entity includes a random access procedureinitiated by a scheduling request procedure. The random access procedurefor the beam failure recovery request may be or may not be considered asa random access procedure initiated by the MAC entity. Since there is acase in which different procedures are performed in the random accessprocedure for the beam failure recovery request and in the random accessprocedure initiated by a scheduling request procedure, the random accessprocedure for the beam failure recovery request and the schedulingrequest may be distinguished. The random access procedure for the beamfailure recovery request and the scheduling request procedure may be therandom access procedure initiated by the MAC entity. In a certainembodiment, the random access procedure initiated by the schedulingrequest procedure may be referred to as the random access procedureinitiated by the MAC entity, and the random access procedure for thebeam failure recovery request may be referred to as the random accessprocedure in response to a notification of a beam failure from the lowerlayer. Hereinafter, the initialization of the random access procedureperformed in the case in which the notification of the beam failure hasbeen received from the lower layer may mean the initialization of therandom access procedure for the beam failure recovery request.

The terminal apparatus 1 performs the contention-based random accessprocedure at the time of an initial access from a state in which noconnection (communication) is established with the base stationapparatus 3 and/or at the time of a scheduling request in a case thatthe terminal apparatus 1 is connected to the base station apparatus 3,and uplink data that can be transmitted or sidelink data that can betransmitted occurs in the terminal apparatus 1. However, theapplications of the contention-based random access are not limitedthereto.

The fact that uplink data that can be transmitted has occurred in theterminal apparatus 1 may include that a buffer status reportcorresponding to the uplink data that can be transmitted has beentriggered. The fact that the uplink data that can be transmitted hasoccurred in the terminal apparatus 1 may include that a schedulingrequest triggered based on the occurrence of the uplink data that can betransmitted is being suspended.

The fact that the sidelink data that can be transmitted has occurred inthe terminal apparatus 1 may include that a buffer status reportcorresponding to the sidelink data that can be transmitted has beentriggered. The fact that the sidelink data that can be transmitted hasoccurred in the terminal apparatus 1 may include that a schedulingrequest triggered based on the occurrence of the sidelink data that canbe transmitted is being suspended.

The non-contention-based random access procedure may be initiated in acase that the terminal apparatus 1 receives information indicatinginitialization of the random access procedure from the base stationapparatus 3. The non-contention-based random access procedure may beinitiated in a case that the MAC layer of the terminal apparatus 1receives a notification of a beam failure from the lower layer.

The non-contention-based random access may be used to quickly establishuplink synchronization between the terminal apparatus 1 and the basestation apparatus 3 in a case that handover or a transmission timing ofthe mobile station apparatus is not effective though the base stationapparatus 3 and the terminal apparatus 1 are being connected to eachother. The non-contention-based random access may be used to transmitthe beam failure recovery request in a case that a beam failure occursin the terminal apparatus 1. However, applications of thenon-contention-based random access are not limited thereto.

However, the information indicating the initialization of the randomaccess procedure may be referred to as a message 0, Msg. 0, an NR-PDCCHorder, a PDCCH order, or the like.

However, in a case that the random access preamble index indicated bythe message 0 is a predetermined value (for example, in a case that allthe bits indicating the index are 0), the terminal apparatus 1 mayperform the contention-based random access procedure of randomlyselecting and transmitting one out of a set of preambles that theterminal apparatus 1 can use.

However, information that is common in a cell may be included in therandom access configuration information, and dedicated information thatdiffers for each terminal apparatus 1 may be included therein.

However, a part of the random access configuration information may beassociated with all SS/PBCH blocks in an SS burst set. However, a partof the random access configuration information may be associated withall of one or a plurality of CSI-RSs set. However, a part of the randomaccess configuration information may be associated with one downlinktransmission beam (or a beam index).

However, a part of the random access configuration information may beassociated with one SS/PBCH block in the SS burst set. However, a partof the random access configuration information may be associated withone CSI-RS set or one of a plurality of CSI-RSs set. However, a part ofthe random access configuration information may be associated with onedownlink transmission beam (or a beam index). However, index information(which may be an SSB index, a beam index, or a QCL configuration index,for example) for specifying the corresponding one SS/PBCH block, oneCSI-RS, and/or one downlink transmission beam may be included in theinformation associated with the one SS/PBCH block, the one CSI-RS,and/or the one downlink transmission beam.

Hereinafter, a PRACH occasion will be described.

A set of one or a plurality of PRACH occasions that can be used totransmit the random access preamble may be specified by a higher layerparameter prach-ConfigIndex provided by the higher layer (higher layersignal). The set of one or a plurality of PRACH occasions that can beused to transmit the random access preamble is specified in accordancewith a PRACH configuration (physical random access channelconfiguration) index provided by prach-ConfigIndex and a predefinedtable (also referred to as a random access channel configuration (PRACHconfig) table). However, the specified one or plurality of PRACHoccasions may be a group of PRACH occasions associated with each of oneor a plurality of SS/PBCH blocks transmitted by the base stationapparatus 3.

However, the PRACH configuration index may be used to configure a periodat which the set of PRACH occasions indicated by the random accessconfiguration table is temporally repeated (PRACH configuration period(physical random access channel configuration period: PRACHconfiguration period)), a subcarrier index that can transmit the randomaccess preamble, a resource block index, a subframe number, a slotnumber, a system frame number, a symbol number, and/or a format of thepreamble.

However, the number of SS/PBCH blocks mapped in each PRACH occasion maybe indicated by a higher layer parameter SSB-perRACH-Occasion providedby the higher layer. In a case that SSB-perRACH-Occasion is a value thatis smaller than 1, one SS/PBCH block is mapped to a plurality ofcontinuous PRACH occasions.

However, the number of random access preambles mapped to each SS/PBCHblock may be indicated by a higher layer parameter cb-preamblePerSSBprovided by the higher layer. The number of random access preamblesmapped to each SS/PBCH block in each PRACH occasion may be calculatedfrom SSB-perRACH-Occasion and cb-preamblePerSSB. The index of the randomaccess preamble mapped to each SS/PBCH block in each PRACH occasion maybe specified from SB-perRACH-Occasion, cb-preamblePerSSB, and SSBindexes.

The SSB indexes may be mapped in the PRACH occasion in accordance withthe following rules.

(1) First, the SSB indexes are mapped in an ascending order of thepreamble indexes for one PRACH occasion. In a case that the number ofpreambles of PRACH occasions is 64, and the number of random accesspreambles mapped to each SS/PBCH block in each PRACH occasion is 32, forexample, the SSB indexes mapped to a certain PRACH occasion are n andn+1.

(2) Second, the SSB indexes are mapped in an ascending order offrequency resource indexes for a plurality of frequency multiplexedPRACH occasions. In a case that two PRACH occasions have been frequencymultiplexed, and the SSB indexes mapped to the PRACH occasion with asmaller frequency resource index are n and n+1, for example, the SSBindexes mapped to the PRACH occasion with a larger frequency resourceindex are n+2 and n+3.

(3) Third, the SSB indexes are mapped in an ascending order of timeresource indexes to a plurality of time multiplexed PRACH occasions in aPRACH slot. In a case that two PRACH occasions have further beenmultiplexed in the time direction in the PRACH slot in addition to theaforementioned example (2), for example, the SSB indexes mapped to thesePRACH occasions are n+4, n+5, n+6, and n+7.

(4) Fourth, the SSB indexes are mapped in an ascending order of theindexes to a plurality of PRACH slots. In a case that RACH occasions arepresent in the next PRACH slot in addition to the aforementioned example(3), for example, the SSB indexes mapped are n+8, n+9, . . . . However,in a case that n+x is greater than the maximum value of the SSB indexesin the aforementioned examples, the values of the SSB indexes arereturned to 0.

FIG. 13 is a diagram illustrating an example of allocation of SSBindexes to PRACH occasions according to the embodiment of the presentinvention. FIG. 13 illustrates an example of a case in which two PRACHslots are present in a certain time period, two PRACH occasions (RO) inthe time direction and two PRACH occasions (RO) in the frequencydirection are present in one PRACH slot, and SSB indexes 0 to 11 arepresent. Two SSB indexes are mapped to one PRACH occasion, the SSBindexes are mapped in accordance with the aforementioned rules (1) to(4), and the SSB indexes are mapped from the SSB index 0 again from theseventh PRACH occasion.

In a case that although the SSB indexes are mapped to each PRACHoccasion, all the SSB indexes (all SS/PBCH blocks transmitted by thebase station apparatus 3) are not mapped even in a case that all thePRACH occasions in a PRACH configuration period specified byprach-ConfigIndex are used, the SSB indexes may be mapped over aplurality of PRACH configuration periods. However, the entire number ofSS/PBCH blocks transmitted by the base station apparatus 3 may beindicated by a higher layer parameter. The period at which the PRACHconfiguration period is repeated a predetermined number of times suchthat all the SSB indexes are mapped at least once will be referred to asan association period. As the number of times the PRACH configurationperiod configuring the association period is repeated, a minimum valuethat satisfies the aforementioned conditions in a predefined set of aplurality of values may be used. The predefined set of a plurality ofvalues may be defined for each PRACH configuration period. However, in acase that all the SSB indexes are mapped to the PRACH occasions in theassociation period, and the number of remaining PRACH occasions isgreater than the number of SS/PBCH blocks, the SSB indexes may be mappedagain. However, in a case that all the SSB indexes are mapped to thePRACH occasions in the association period, and the number of remainingPRACH occasions is smaller than the number of SS/PBCH blocks, the SSBindexes may not be mapped to the remaining PRACH occasions. A cycle atwhich the PRACH occasions are allocated to all the SSB indexes once willbe referred to as an SSB index allocation cycle. In a case thatSSB-perRACH-Occasion is equal to or greater than 1, each of the SSBindexes is mapped to one PRACH occasion in one SSB index allocationcycle. In a case that SSB-perRACH-Occasion is a value that is smallerthan 1, each SSB index is mapped to 1/SSB-perRACH-Occasion PRACHoccasions in one SSB index allocation cycle. The terminal apparatus 1may specify the association period based on the PRACH configurationperiod indicated by the PRACH configuration index and the number ofSS/PBCH blocks specified by the higher parameter provided by the higherlayer (higher layer signal).

Each of one or a plurality of random access preamble groups included inrandom access configuration information may be associated for eachreference signal (for example, an SS/PBCH block, a CSI-RS, or a downlinktransmission beam). The terminal apparatus 1 may select a random accesspreamble group based on the received reference signal (for example, theSS/PBCH block, the CSI-RS, or the downlink transmission beam).

However, the random access preamble group associated with each SS/PBCHblock may be specified by one or a plurality of parameters notified fromthe higher layer. The one parameter or one of the plurality ofparameters may be one index (for example, a start index) of one or aplurality of available preambles. The one parameter or the one of theplurality of parameters may be the number of preambles that can be usedfor a contention-based random access per SS/PBCH block. The oneparameter or the one of the plurality of parameters may be a total ofthe number of preambles that can be used for the contention-based randomaccess per SS/PBCH block and the number of preambles that can be usedfor the non-contention-based random access. The one parameter or the oneof the plurality of parameters may be the number of SS/PBCH blocksassociated with one PRACH occasion.

However, the terminal apparatus 1 may receive one or a plurality ofdownlink signals, each of which is transmitted using one downlinktransmission beam, receive random access configuration informationassociated with one of the downlink signals, and perform the randomaccess procedure based on the received random access configurationinformation. The terminal apparatus 1 may receive one or a plurality ofSS/PBCH blocks in the SS burst set, receive random access configurationinformation associated with one of the SS/PBCH blocks, and perform therandom access procedure based on the received random accessconfiguration information. The terminal apparatus 1 may receive one or aplurality of CRI-RSs, receive random access configuration informationassociated with one of the CRI-RSs, and perform the random accessprocedure based on the received random access configuration information.

One or a plurality of pieces of random access configuration informationmay include one random access channel configuration (RACH-Config) and/orone physical random access channel configuration (PRACH-Config).

Parameters related to the random access for each reference signal may beincluded in the random access channel configuration.

Parameters (such as an index of PRACH configuration, a PRACH occasion,and the like) related to the physical random access channel for eachreference signal may be included in the physical random access channelconfiguration.

One piece of random access configuration information may indicateparameters related to a random access corresponding to one referencesignal, and a plurality of pieces of random access configurationinformation may indicate parameters related to a plurality of randomaccesses corresponding to a plurality of reference signals.

One piece of random access configuration information may indicateparameters related to a physical random access corresponding to onereference signal, and may indicate parameters related to a plurality ofrandom accesses corresponding to a plurality of reference signals.

Random access configuration information corresponding to a referencesignal (random access channel configuration corresponding to thereference signal, physical random access channel configurationcorresponding to the reference signal) may be selected in response toselection of the corresponding reference signal.

However, the terminal apparatus 1 may receive one or a plurality ofpieces of random access configuration information from a base stationapparatus 3 that transmits the random access preamble and/or a basestation apparatus 3 that is different from the transmission receptionpoints 4 and/or the transmission reception points 4. For example, theterminal apparatus 1 may transmit the random access preamble to a secondbase station apparatus 3 based on at least one piece of random accessconfiguration information received from a first base station apparatus3.

However, the base station apparatus 3 may determine the downlinktransmission beam to be applied in a case that the downlink signal istransmitted to the terminal apparatus 1, by receiving the random accesspreamble transmitted by the terminal apparatus 1. The terminal apparatus1 may transmit the random access preamble using a PRACH occasionindicated by the random access configuration information associated witha certain downlink transmission beam. The base station apparatus 3 maydetermine the downlink transmission beam to be applied in a case thatthe downlink signal is transmitted to the terminal apparatus 1, based onthe random access preamble received from the terminal apparatus 1 and/orthe PRACH occasion in which the random access preamble is received.

The base station apparatus 3 transmits an RRC parameter including one ora plurality of pieces of random access configuration information (whichmay include random access resources) as an RRC message to the terminalapparatus 1.

The terminal apparatus 1 may select one or a plurality of availablerandom access preambles and/or one or a plurality of available PRACHoccasions used for the random access procedure based on properties of atransmission path with the base station apparatus 3. The terminalapparatus 1 may select one or a plurality of available random accesspreambles and/or one or a plurality of PRACH occasions used for therandom access procedure based on properties of the transmission path(which may be a reference signal reception power (RSRP), for example)measured by a reference signal (an SS/PBCH bock and/or a CSI-RS, forexample) received from the base station apparatus 3.

In the present embodiment, an uplink resource allocation type 0 and anuplink resource allocation type 1 are supported for uplink resourceallocation. In the uplink resource allocation type 0 (uplink type 0resource allocation), resource block assignment information includes abit map indicating Resource Block Groups (RBGs) allocated to theterminal apparatus 1. The resource block groups are sets of continuousvirtual resource blocks and may be defined from parameters of the higherlayer.

Hereinafter, the uplink resource allocation type 1 (uplink type 1resource allocation) will be described.

The resource block assignment information indicates sets ofnon-interleave virtual resource blocks continuously allocated with anactive BWP with a size N^(size) _(BWP) to the scheduled terminalapparatus 1. Here, the size N^(size) _(BWP) is the number of resourceblocks indicating the bandwidth of the active UL BWP. In a case that theDCI format 0_0 has been detected in the type 0-PDCCH common search spaceset of CORESET#0, the size N^(size) _(BWP) indicates the bandwidth ofthe initial UL BWP.

The uplink type 1 resource assignment field includes a start resourceblock (RB_(start), start virtual resource block) and a ResourceIndication Value (RIV) corresponding to the number (L_(RBs)) of theresource blocks continuously allocated. In other words, the resourceindication value RIV is indicated in the resource assignment field.RB_(start) indicates a start position of the allocated resource blocks.L_(RBs) indicates the number (the length, the size) of the resourceblocks of the allocated resources. The resource indication value RIVindicates the resources allocated to a corresponding UL BWP as a target.The UL BWP as a target may be the UL BWP to which the resourceassignment (resource assignment field) is applied. The terminalapparatus 1 fixes the UL BWP to which the resource assignment is appliedfirst and then determines resource allocation in the fixed UL BWP. Inother words, the value of RIV is calculated by the size (N^(size)_(BWP)) of the UL BWP to which the resource assignment is applied, thestart resource block (RB_(start)), and the number (L_(RBs)) of resourceblocks continuously allocated. In other words, the terminal apparatus 1calculates the start position of the resource blocks allocated with theUL BWP and the number of resource blocks continuously allocated, basedon the value of the RIV and N^(size) _(BWP) indicated in the resourceassignment field. In other words, the terminal apparatus 1 interpretsbits of the resource assignment field for the UL BWP to which theresource assignment is applied. The base station apparatus 3 determinesresource assignment in the UL BWP applied to the terminal apparatus 1,generates RIV based on the size of the applied UL BWP, and transmitsresource assignment including a bit sequence indicating the RIV to theterminal apparatus 1.

The terminal apparatus 1 specifies the resource block allocation in thefrequency direction (in the PUSCH) of the applied UL BWP, based on thebit sequence in the resource assignment field.

FIG. 12 is a diagram illustrating an example in which an RIV iscalculated.

In FIG. 12(A), N^(size) _(BWP) is the number of resource blocksindicating the bandwidth of the active UL BWP. The value of RIV iscalculated based on the number N^(size) _(BWP) of the resource blocksindicating the bandwidth of the initial BWP, the start positionRB_(start) of the resource blocks, and the number of L_(RBs) of theresource blocks continuously allocated. RB_(start) is the start positionof the resource blocks for the active UL BWP. L_(RBs) is the number ofresource blocks continuously allocated to the active BWP. In thismanner, the resources allocated to the active BWP is specified by thestart position RB_(start) of the resource blocks and the number L_(RBs)of the resource blocks continuously allocated. In a case that the DCIformat has been detected in a common search space set (the type 1-PDCCHcommon search space set), the number of resource blocks indicating thebandwidth of the initial UL BWP is used for N^(size) _(BWP) in FIG.12(A).

In FIG. 12(B), N^(nitial) _(BWP) is the number of resource blocksindicating the bandwidth of the initial BWP (UL BWP). N^(active) _(BWP)is the number of resource blocks indicating the bandwidth of the activeBWP (UL BWP). The value of RIV is calculated based on the numberN^(nitial) _(BWP) of the resource blocks that indicates the bandwidth ofthe initial BWP, the start position RB′_(start) of the resource blocks,and the number L′_(RBs) of the resource blocks continuously allocated.RB′_(start) is the start position of the resource blocks for the initialBWP. L′_(RBs) is the number of resource blocks continuously allocated tothe initial BWP. Multiplication of RB′_(start) and a coefficient K isRB_(start). Multiplication of L′_(RBs) and a coefficient K is L_(RBs).The value of the coefficient K is calculated based on the bandwidth ofthe initial BWP and the bandwidth of the active BWP. In a case thatN^(active) _(BWP) is greater than N^(nitial) _(BWP), the value of K is amaximum value that satisfies K<=Floor(N^(active) _(BWP)/N^(nitial)_(BWP)) in a set {1, 2, 4, 8}. Here, the function Floor(A) outputs themaximum number that does not exceed A. In a case that N^(active) _(BWP)is equal to or less than N^(nitial) _(BWP), the value of K is 1. In thismanner, the resources allocated to the active BWP is specified by thestart position RB_(start) of the resource blocks and the number L_(RBs)of the resource blocks continuously allocated.

The resource specification method in FIG. 12(B) may be used for a casein which although the size of the DCI format in USS (or the size of thefrequency domain resource assignment field included in the DCI format)is derived by the initial BWP, the size is applied to the active BWP.The DCI format may be the DCI format 0_0 and/or the DCI format 0_1.

FIG. 11 is a diagram illustrating an example for explaining the uplinkresource allocation type 1 for BWPs.

In FIG. 11, one initial UL BWP (1101) and two additional UL BWPs (1102and 1103) are configured for the terminal apparatus 1. As describedabove, common resource blocks n_(PRB) are resource blocks numbered in anascending order from 0 at each subcarrier spacing configuration μ from apoint A. In other words, 1114 is a common resource block (commonresource block 0) to which the number 0 is applied. In the subcarrierspacing configuration μ, the center of the subcarrier index 0 of thecommon resource block 0 (common resource block index 0, n_(CRB)#0)coincides with the point A. 1104 is the start position of the carrier inthe subcarrier spacing configuration μ and is provided from a parameterOffsetToCarrier of the higher layer. In other words, the parameterOffsetToCarrier of the higher layer is an offset between the point A andthe lowest available subcarrier of the carrier in the frequency domain.The offset (1115) indicates the number of resource blocks in thesubcarrier spacing configuration μ. In other words, in a case that thesubcarrier spacing configuration μ differs, the bandwidth of the offsetin the frequency domain differs. In the subcarrier spacing configurationμ, 1104 may be the position of the resource block at which the carrierstarts. Physical resource blocks are resource blocks numbered in anascending order from 0 for each BWP. In the subcarrier spacingconfiguration μ of each BWP index i, a relationship between a physicalresource block n_(PRB) of the BWP index i and the common resource blockn_(CRB) is provided by (Expression 3) n_(CRB)−n_(PRB)+N^(start)_(BWP, i). In the subcarrier spacing configuration μ of each BWP,N^(start) _(BWP, i) is the number of common resource blocks at which theBWP index i is started with respect to the common resource block index0. N^(size) _(BWP, i) is the number of resource blocks indicating thebandwidth of the BWP of the index i in the subcarrier spacingconfiguration μ of the BWP index i.

The position and the bandwidth of the BWP in the frequency domain areprovided by a parameter locationAndBandwidth of the higher layer.Specifically, the first physical resource block (physical resource blockindex 0) of the BWP index i and the number of continuous physicalresource blocks are provided by the parameter locationAndBandwidth ofthe higher layer. The value indicated by the parameterlocationAndBandwidth of the higher layer is interpreted as the value ofRIV for the carrier. As in FIG. 12(A), N^(size) _(BWP) is set to 275.Also, RB_(start) and L_(RBs) identified by the value of RIV indicate thefirst physical resource block (physical resource block index 0) of theBWP and the number of continuous physical resource blocks indicating thebandwidth of the BWP. The first physical resource block of BWP index iis a physical resource block offset with respect to the physicalresource block (1104) indicated by a parameter OffsetToCarrier of thehigher layer. The number of resource blocks indicating the bandwidth ofthe BWP index i is N^(size) _(BWP, i). N^(start) _(BWP, i) of the BWPindex i is provided from the first physical resource block of the BWPindex i and the offset indicated by the parameter OffsetToCarrier of thehigher layer.

In other words, 1105 is the physical resource block index 0 (n_(PRB)#0)in UL BWP#0 (1101) in the subcarrier spacing configuration μ of ULBWP#0, in FIG. 11. A relationship between the physical resource blockand the common resource block in UL BWP#0 is provided byn_(CRB)=n_(PRB)+N^(start) _(BWP, 0). In the subcarrier spacingconfiguration μ of UL BWP#0, N^(start) _(BWP, 0) (1107) is the commonresource block at which UL BWP#0 is started with respect to the commonresource block index 0. N^(size) _(BWP, 0) (1106) is the number ofresource blocks indicating the bandwidth of UL BWP#0 in the subcarrierspacing configuration μ of UL BWP#0.

In FIG. 11, 1108 is the physical resource block index 0 (n_(PRB)#0) inUL BWP#1 (1102) in the subcarrier spacing configuration μ of UL BWP#1. Arelationship between the physical resource block and the common resourceblock in UL BWP#1 is provided by n_(CRB)=n_(PRB)+N^(start) _(BWP, 1). Inthe subcarrier spacing configuration μ of UL BWP#1, N^(start) _(BWP, 1)(1110) is a common resource block at which UL BWP#1 for the commonresource block index 0 is started. N^(size) _(BWP, 1) (1109) is thenumber of resource blocks indicating the bandwidth of UL BWP#0 in thesubcarrier spacing configuration μ of UL BWP#1.

In FIG. 11, 1111 is the physical resource block index 0 (n_(PRB)#0) inUL BWP#2 in the subcarrier spacing configuration of UL BWP#2 (1102). Arelationship between the physical resource block and the common resourceblock in UL BWP#2 is provided by n_(CRB)=n_(PRB)+N^(start) _(BWP, 2). Inthe subcarrier spacing configuration μ of UL BWP#2, N^(start) _(BWP, 2)(1113) is a common resource block at which UL BWP#2 is started withrespect to the common resource block index 0. N^(size) _(BWP, 2) (1112)is the number of resource blocks indicating the bandwidth of UL BWP#2 inthe subcarrier spacing configuration μ of UL BWP#2.

As can be seen from FIG. 11, the start position (starting commonresource block, N^(start) _(BWP)) and the number of resource blocks(N^(size) _(BWP)) differ for each BWP configured for the terminalapparatus 1. The terminal apparatus 1 needs to determine the UL BWP towhich the resource assignment is applied in a case that the terminalapparatus 1 interprets the RIV indicated by the bits of the resourceassignment field. In other words, the terminal apparatus 1 can determinethe UL BWP to which the resource assignment is applied, interpret theRIV based on N^(size) _(BWP, i) of the determined UL BWP, and calculatethe start resource block (RB_(start)) and the number of resource blocks(L_(RBs)) continuously allocated. Calculated RB_(start) indicates theposition at which the resources allocated are started with reference tothe physical resource block index 0 of the UL BWP to which the resourceassignment is applied. In a case that the resource assignment is appliedto different UL BWPs even in a case that the calculated value ofRB_(start) is the same, the positions of the starting common resourceblocks differ.

Also, in a case that the size N^(size) _(BWP) of the UL BWP to which theresource assignment is applied differs, the number of bits of theresource assignment indicating the value of RIV also differs. The bitsof the resource block assignment field that can indicate the value ofRIV is provided by Ceiling(log₂(N^(size) _(BWP)(N^(size) _(BWP)+1)/2)).

FIG. 8 is a diagram illustrating an example of a random access procedureof the terminal apparatus 1 according to the present embodiment.

Message 1 (S801)

In S801, the terminal apparatus 1 transmits a random access preamble tothe base station apparatus 3 via a PRACH. The transmitted random accesspreamble may be referred to as a message 1 (Msg1). The transmission ofthe random access preamble will also be referred to as PRACHtransmission. The random access preamble is configured to notifyinformation to the base station apparatus 3 using one sequence among aplurality of sequences. For example, sixty four types (the numbers ofrandom access preamble indexes range from 1 to 64) of sequences areprepared. In a case that sixty four types of sequences are prepared, itis possible to indicate 6-bit information (which may be ra-PreambleIndexor a preamble index) for the base station apparatus 3. The informationmay be indicated as a random access preamble identifier (Random AccessPreamble Identifier, RAPID).

In a case of a contention-based random access procedure, an index of arandom access preamble is randomly selected by the terminal apparatus 1itself. In the contention-based random access procedure, the terminalapparatus 1 selects SS/PBCH blocks that have SS/PBCH block RSRPexceeding a configured threshold value and performs selection of apreamble group. In a case that a relationship between the SS/PBCH blockand the random access preamble has been configured, the terminalapparatus 1 randomly selects ra-PreambleIndex from one or a plurality ofrandom access preambles associated with the selected SS/PBCH block andthe selected preamble group and sets selected ra-PreambleIndex to thepreamble index (PREAMBLE_INDEX). Also, the selected SS/PBCH block andthe selected preamble group may be split into two subgroups based on thetransmission size of the message 3, for example. The terminal apparatus1 may randomly select a preamble index from the subgroup correspondingto a small transmission size of the message 3 in a case that thetransmission size of the message 3 is small, or may randomly select apreamble index from the subgroup corresponding to a large transmissionsize of the message 3 in a case that the transmission size of themessage 3 is large. The index in the case in which the message size issmall is typically selected in a case that properties of thetransmission path are poor (or the distance between the terminalapparatus 1 and the base station apparatus 3 is far), and the index inthe case in which the message size is large is selected in a case thatthe properties of the transmission path are good (or the distancebetween the terminal apparatus 1 and the base station apparatus 3 isclose).

In a case of the non-contention-based random access procedure, an indexof the random access preamble is selected based on information receivedby the terminal apparatus 1 from the base station apparatus 3. Here, theinformation received by the terminal apparatus 1 from the base stationapparatus 3 may be included in the PDCCH. In a case that all the valuesof bits of the information received from the base station apparatus 3are 0, the contention-based random access procedure is executed by theterminal apparatus 1, and the index of the random access preamble isselected by the terminal apparatus 1 itself.

Message 2 (S802)

Next, the base station apparatus 3 that has received the message 1generates a RAR message including an uplink grant (Random AccessResponse Grant, RAR UL grant) for indicating transmission for theterminal apparatus 1 and transmits a random access response includingthe generated RAR message to the terminal apparatus 1 in DL-SCH in S802.In other words, the base station apparatus 3 transmits, in the PDSCH ina primary cell, the random access response including the RAR messagecorresponding to the random access preamble transmitted in S801. ThePDSCH corresponds to a PDCCH including RA-RNTI. This Ra-RNTI iscalculated by RA-RNTI=1+s_id+14×t_id+14×80×f_id+14×80×8×ul_carrier_id.Here, s_id is an index of the first OFDM symbol in the transmitted PRACHand is a value of 0 to 13. t_id is an index of the first slot of thePRACH in the system frame and is a value of 0 to 79. f_id is an index ofthe PRACH in the frequency domain and is a value of 0 to 7.ul_carrier_id is an uplink carrier used for Msg1 transmission.ul_carrier_id for the NUL carrier is 0 while ul_carrier_id for the SULcarrier is 1.

The random access response may be referred to as a message 2 or Msg2.Also, the base station apparatus 3 includes, in the message 2, a randomaccess preamble identifier corresponding to the received random accesspreamble and an RAR message (MAC RAR) corresponding to the identifier.The base station apparatus 3 calculates a deviation in transmissiontiming between the terminal apparatus 1 and the base station apparatus 3from the received random access preamble and includes, in the RARmessage, transmission timing adjustment information (Timing Advance (TA)command) for adjusting the deviation. The RAR message includes at leasta random access response grant field mapped to the uplink grant, aTemporary Cell Radio Network Temporary Identifier (C-RNTI) field towhich Temporary C-RNTI is mapped, and a Timing Advance (TA) command. Theterminal apparatus 1 adjusts the timing of the PUSCH transmission basedon the TA command. The timing of the PUSCH transmission may be adjustedfor each cell group. The base station apparatus 3 includes, in themessage 2, the random access preamble identifier corresponding to thereceived random access preamble.

In order to respond to PRACH transmission, the terminal apparatus 1detects (monitors) the DCI format 1_0 to which a CRC parity bitscrambled with the corresponding RA-RNTI is added, during a time periodof a random access response window. The time period of the random accessresponse window (window size) is provided by a higher layer parameterra-ResponseWindow. The window size is the number of slots based on thesubcarrier spacing of the Type1-PDCCH common search space.

In a case that the terminal apparatus 1 detects the DCI format 1_0 towhich the CRC scrambled with RA-RNTI is added and the PDSCH includingone DL-SCH transport block in the time period of the window, then theterminal apparatus 1 passes the transport block to the higher layer. Thehigher layer analyzes the transport block for the random access preambleidentifier (RAPID) related to the PRACH transmission. In a case that thehigher layer identifies RAPID included in the RAR message of the DL-SCHtransport block, the higher layer indicates the uplink grant for thephysical layer. The identification means that RAPID included in thereceived random access response and RAPID corresponding to thetransmitted random access preamble are the same. The uplink grant willbe referred to as a random access response uplink grant (RAR UL grant)in the physical layer. In other words, the terminal apparatus 1 canspecify the RAR message (MAC RAR) directed to the apparatus itself fromthe base station apparatus 3, by monitoring the random access response(message 2) corresponding to the random access preamble identifier.

(i) In a case that the terminal apparatus 1 does not detect the DCIformat 1_0 to which CRC scrambled with RA-RNTI is added in the timeperiod of the window, or (ii) in a case that the terminal apparatus 1does not properly receive the DL-SCH transport block in the PDSCH in thetime period of the window, or (iii) in a case that the higher layer doesnot identify RAPID related to the PRACH transmission, the higher layerprovides an indication to transmit the PRACH to the physical layer.

In a case that the random access preamble identifier corresponding tothe transmitted random access preamble is included in the receivedrandom access response, and the random access preamble has been selectedbased on the information received by the terminal apparatus 1 from thebase station apparatus 3, the terminal apparatus 1 regards thenon-contention-based random access procedure as having successfully beencompleted and transmits the PUSCH based on the uplink grant included inthe random access response.

In a case that the random access preamble identifier corresponding tothe transmitted random access preamble is included in the receivedrandom access response, and the random access preamble has been selectedby the terminal apparatus 1 itself, TC-RNTI is set to the value of theTC-RNTI field included in the received random access response, and therandom access message 3 is transmitted in the PUSCH based on the uplinkgrant included in the random access response. The PUSCH corresponding tothe uplink grant included in the random access response is transmittedin a serving cell in which the corresponding preamble has beentransmitted in the PRACH.

The RAR uplink (UL) grant is used to schedule the PUSCH transmission(Msg3 PUSCH). The terminal apparatus 1 performs the transmission of themessage 3 based on the RAR UL grant. FIG. 9 is a diagram illustrating anexample of fields included in the RAR UL grant.

In a case that the value of a frequency hopping flag is 0 in FIG. 9, theterminal apparatus 1 transmits Msg3 PUSCH with no frequency hopping. Ina case that the value of the frequency hopping flag is 1, the terminalapparatus 1 transmits Msg3 PUSCH that accompanies the frequency hopping.

The ‘Msg3 PUSCH time resource allocation’ field is used to indicateresource allocation in the time domain for the Msg3 PUSCH.

The ‘MCS’ field is used to determine an MCS index for the Msg3 PUSCH.

The ‘TPC command for Msg3 PUSCH’ field is used for configuration of atransmission power of the Msg3 PUSCH.

In the contention-based random access procedure, the ‘CSI request’ fieldis reserved. In the non-contention-based random access procedure, the‘CSI request’ field is used to determine whether or not an aperiodic CSIreport is included in the PUSCH transmission.

Hereinafter, interpretation of the ‘Msg3 PUSCH frequency resourceallocation’ field will be described. The field is used for resourceallocation for the PUSCH transmission of the message 3. The ‘Msg3 PUSCHfrequency resource allocation’ (Msg3 PUSCH frequency resourceassignment) field may be referred to as fixed size resource blockassignment. In other words, the Msg3 PUSCH frequency resource assignmenthas a fixed number of bits regardless of the bandwidth of the UL BWPconfigured for the terminal apparatus 1. The terminal apparatus 1truncates or inserts bits with respect to the Msg3 PUSCH frequencyresource assignment based on the number (N^(size) _(BWP)) of theresource blocks indicating the bandwidth of the UL BWP to which theresource assignment is applied. In addition, the terminal apparatus 1can adapt the bits to the bandwidth of the UL BWP to which the resourceassignment is applied by truncating or inserting the bits with respectto the Msg3 PUSCH frequency resource assignment. N^(size) _(BWP) is thenumber of resource blocks indicating the bandwidth of the UL BWP towhich the resource assignment is applied. In S802 described below, theUL BWP to which the resource assignment is applied is the UL BWP towhich the Msg3 PUSCH frequency resource assignment is applied.

FIG. 10 is a diagram illustrating an example of interpretation of the“Msg3 PUSCH frequency resource allocation’ field according to thepresent embodiment.

1001 in FIG. 10(A) denotes the ‘Msg3 PUSCH frequency resourceallocation” field having specific 14 bits. 1002 denotes N_(UL, hop)hopping bits. 1003 denotes bits remaining after excluding theN_(UL, hop) hopping bits from 1001 and is (14−N_(UL, hop)) bits. Inother words, 14 bits in 1001 include 1002 and 1003. The bit number ofN_(UL, hop) hopping bits is provided based on the value indicated in the“Frequency hopping flag” field and/or the bandwidth of N^(size) _(BWP).For example, the bit number of the N_(UL, hop) example may be 1 bit in acase that the size of N^(size) _(BWP) is smaller than a predeterminedvalue of the number of resource blocks. The bit number of theN_(UL, hop) example may be 2 bits in a case that the size of N^(size)_(BWP) is equal to or greater than the predetermined value of the numberof resource blocks. The predetermined value of the number of resourceblocks may be fifty. Description of N^(size) _(BWP) will be given later.

As described above, N_(UL, hop) hoping bits are 0 bits in a case thatthe value of the frequency hopping flag is 0. In this case, 1003 is 1001and has 14 bits. In a case that the value of the frequency hopping flagis 1, the bit number of the N_(UL, hop) hoping bits may be provided as 1bit or 2 bit based on whether the value of N^(size) _(BWP) has exceededa predetermined value Y of the number of resource blocks. In a case thatN^(size) _(BWP) is smaller than the predetermined value Y of the numberof resource blocks, N_(UL, hop) hoping bits may be provided as 1 bit. Ina case that N^(size) _(BWP) is equal to or greater than thepredetermined value Y of the number of resource blocks, the N_(UL, hop)hoping bits may be provided as 2 bits. In other words, 1003 has 12 bitsor 13 bits.

FIG. 10(B) is an example illustrating an example in which bits of the‘Msg3 PUSCH frequency resource allocation’ field are truncated in a casethat N^(size) _(BWP) is smaller than or equal to a predetermined value Xof the number of resource blocks.

In FIG. 10(B), the terminal apparatus 1 truncates the bits of the Msg3PUSCH frequency resource assignment by b bits from the least significantbit (LSB) in a case that N^(size) _(BWP) is smaller than or equal to thepredetermined value X of the number of resource blocks. In other words,b bits are the number of bits to be truncated. The value of b iscalculated by (Expression 1) b=Ceiling(log₂(N^(size) _(BWP)(N^(size)_(BWP)+1)/2)). Here, the function Ceiling(A) outputs a minimum integerthat is not less than A. The Msg3 PUSCH frequency resource assignment tobe truncated may be referred to as resource block assignment to betruncated. The terminal apparatus 1 may interpret the resource blockassignment to be truncated in accordance with a typical rule for the DCIformat 0_0.

In FIG. 10(B), 1004 denotes Msg3 PUSCH frequency resource assignmenthaving 14 bits. 1005 denotes N_(UL, hop) hopping bits. 1006 denotes bitsother than the N_(UL, hop) hopping bits in the Msg3 PUSCH frequencyresource assignment. 1008 denotes the resource block assignment to betruncated. The bit number of 1008 is b bits. The bit number of 1007 is14−b.

FIG. 10(C) is a diagram illustrating an example in which bits of the‘Msg3 PUSCH frequency resource allocation’ field are inserted in a casethat the bandwidth of N^(size) _(BWP) is greater than the predeterminedvalue X of the number of resource blocks.

In FIG. 10(C), 1009 denotes Msg3 PUSCH frequency resource assignmenthaving 14 bits. 1010 denotes N_(UL, hop) hopping bits. 1012 denotes bitsremaining after excluding N_(UL, hop) hopping bits from the Msg3 PUSCHfrequency resource assignment. The bit number of 1012 is(14−N_(UL, hop)) bits. In a case that N^(size) _(BWP) is greater thanthe predetermined value X of the number of resource blocks, the terminalapparatus 1 inserts b most significant (MSB) bits set to the value ‘0”after the N_(UL, hop) hopping bits in the Msg3 PUSCH frequency resourceassignment. In other words, b bits represent the number of bits to beinserted. The value of b is calculated by (Expression 2)b=(Ceiling(log₂(N^(size) _(BWP)(N^(size) _(BWP)+1)/2))−Z). The value ofZ may be 14. The Msg3 PUSCH frequency resource assignment into which theb bits are inserted may be referred to as a resource block assignment tobe expanded. The terminal apparatus 1 may interpret the resource blockassignment to be expanded in accordance with a typical rule for the DCIformat 0_0. In FIG. 10(C), the bit number of 1011 is b bits. 1009denotes the expanded resource block assignment. The bit number of 1009is a sum of 14 bits of the Msg3 PUSCH frequency resource assignment andb bits.

As described above, an initial BWP including at least one DL BWP and oneUL BWP is configured for the terminal apparatus 1. Further, a maximum offour additional BWPs are configured for the terminal apparatus 1. Also,the size (N^(size) _(BWP)) of each UL BWP configured for the terminalapparatus 1 may be different. The size N^(size) _(BWP) of the UL BWP isthe number of resource blocks indicating the bandwidth of thecorresponding UL BWP. In a case that resource allocation is specified,the terminal apparatus 1 fixes the UL BWP to which the resourceassignment is applied first and then determines resource allocation inthe fixed UL BWP.

The terminal apparatus 1 determines the UL BWP to which the resourceassignment is applied in a case that bits are truncated or inserted withrespect to the Msg3 PUSCH frequency resource assignment. In other words,the terminal apparatus 1 determines N^(size) _(BWP) indicating thebandwidth of the UL BWP used in a case that bits are truncated orinserted with respect to the Msg3 PUSCH frequency resource assignment,based on the UL BWP to which the resource assignment is applied.

Hereinafter, the determination method of N^(size) _(BWP) indicating thebandwidth of the UL BWP (UL BWP as a target of interpretation) to whichthe resource assignment in the present embodiment will be described. Thebase station apparatus 3 determines N^(size) _(BWP) in the random accessprocedure, generates the RIV using the determined N^(size) _(BWP), fixesthe bit sequence to be included in the field of the frequency resourceassignment, and transmits the PUSCH frequency resource assignment to theterminal apparatus 1.

As described above, the terminal apparatus 1 monitors the DCI format towhich the CRC scrambled with RA-RNTI or TC-RNTI is added in the searchspace (type1-PDCCH common search space set) for the random accessprocedure. The terminal apparatus 1 receives a random access response bymonitoring the DCI format to which the CRC scrambled with the RA-RNTI isapplied in the search space set. The configuration information of theCORESET for the type1-PDCCH common search space set is indicated for theterminal apparatus 1.

According to an aspect of the present embodiment, in thecontention-based random access procedure, the terminal apparatus 1 maydetermine, as a UL BWP to which the resource assignment is applied, a ULBWP with the same BWP identifier as that of the DL BWP for which theconfiguration information of the CORESET associated with the searchspace (type1-PDCCH common search space set) for the random accessprocedure has been configured. In other words, in the contention-basedrandom access procedure, N^(size) _(BWP) is the number of resourceblocks indicating the bandwidth of the UL BWP with the same BWPidentifier as the DL BWP for which the configuration information of theCORESET associated with the type1-PDCCH common search space set has beenconfigured. Also, bits are truncated or inserted with respect to theMsg3 PUSCH frequency resource assignment using the terminal apparatus 1,the determined N^(size) _(BWP). Bits of the resource block assignment tobe truncated or of the resource block assignment to be expandedindicates the value of RIV. The terminal apparatus 1 can calculateRB_(start) and L_(RBs) using determined N^(size) _(BWP) as N^(size)_(BWP) in FIG. 12(A). RB_(start) calculated from the value of RIVindicates the start position of the resource allocated with reference tothe physical resource block index 0 of the UL BWP to which the resourceassignment is applied. In other words, numbering of the resourceallocation indicated by the RAR UL grant starts in an ascending orderfrom the physical resource block index 0 (the lowest number of thephysical resource block of the UL BWP to which the resource assignmentis applied) corresponding to the UL BWP to which the resource assignmentis applied.

According to an aspect of the present embodiment, in thecontention-based random access procedure, the terminal apparatus 1determines either the initial UL BWP or the active UL BWP as the UL BWPto which the resource assignment is applied, based on whether the DL BWPfor which the configuration information of the CORESET associated withthe type1-PDCCH common search space set has been configured is theinitial DL BWP. In a case that the DL BWP for which the configurationinformation of the CORESET associated with the type1-PDCCH common searchspace set has been configured is the initial DL BWP, for example, theterminal apparatus 1 may determine the initial UL BWP as the UL BWP towhich the resource assignment is applied. Also, in a case that the DLBWP for which the configuration information of the CORESET associatedwith the type1-PDCCH common search space set has been configured is notthe initial DL BWP, the terminal apparatus 1 may determine the active ULBWP as the UL BWP to which the resource assignment is applied. N^(size)_(BWP) is the number of resource blocks indicating the bandwidth of theUL BWP. In addition, bits are truncated or inserted with respect to theMsg3 PUSCH frequency resource assignment using N^(size) _(BWP) that isthe bandwidth of the UL BWP determined to be the UL BWP to which theterminal apparatus 1, the resource assignment are applied.

According to an aspect of the present embodiment, in thecontention-based random access procedure, the terminal apparatus 1determines either the initial UL BWP or the active UL BWP as the UL BWPto which the resource assignment is applied, based on whether theCORESET associated with the type1-PDCCH common search space set is thecommon CORESET. In a case that the CORESET associated with thetype1-PDCCH common search space set is the common CORESET, for example,the terminal apparatus 1 may determine the initial UL BWP as the UL BWPto which the resource assignment is applied. In a case that the CORESETassociated with the type1-PDCCH common search space set is not thecommon CORESET, the terminal apparatus 1 may determine the active UL BWPas the UL BWP to which the resource assignment is applied. N^(size)_(BWP) is the number of resource blocks indicating the bandwidth of theUL BWP to which the resource assignment is applied. Also, bits aretruncated or inserted with respect to the Msg3 PUSCH frequency resourceassignment using the terminal apparatus 1, the determined N^(size)_(BWP).

According to an expansion of the aforementioned aspect, in thecontention-based random access procedure, the terminal apparatus 1determines either the initial UL BWP or the active UL BWP as the UL BWPto which the resource assignment is applied, based on whether theCORESET associated with the type1-PDCCH common search space set isCORESET#0. In a case that the CORESET associated with the type1-PDCCHcommon search space set is CORESET#0, for example, the terminalapparatus 1 may determine the initial UL BWP as the UL BWP to which theresource assignment is applied. In a case that the CORESET associatedwith the type1-PDCCH common search space set is not CORESET#0, theterminal apparatus 1 may determine the active UL BWP as the UL BWP towhich the resource assignment is applied. In a case that the CORESETassociated with the type1-PDCCH common search space set is an additionalcommon CORESET, the terminal apparatus 1 may determine the UL BWP withthe same BWP identifier as the DL BWP for which the additional commonCORESET has been configured as the UL BWP to which the resourceassignment is applied. In other words, in a case that the terminalapparatus 1, the additional common CORESET have been configured for theinitial DL BWP, the initial UL BWP may be determined to be the UL BWP towhich the resource assignment is applied. In a case that the terminalapparatus 1, the additional common CORESET have been configured for theadditional DL BWP, the UL BWP with the same BWP identifier as theadditional DL BWP may be determined to be the UL BWP to which theresource assignment is applied.

According to an aspect of the present embodiment, in thecontention-based random access procedure, the terminal apparatus 1 mayalways determine the initial UL BWP as the UL BWP to which the resourceassignment is applied. In other words, N^(size) _(BWP) is the number ofresource blocks indicating the bandwidth of the initial UL BWP in thecontention-based random access procedure. Also, bits are truncated orinserted with respect to the Msg3 PUSCH frequency resource assignmentusing the terminal apparatus 1, the determined N^(size) _(BWP). Bits ofthe resource block assignment to be truncated or of the resource blockassignment to be expanded indicates the value of RIV. The terminalapparatus 1 fixes that the RIV is to be generated using determinedN^(size) _(BWP) as N^(size) _(BWP) in FIG. 12(A). The RIV is generatedfrom RB_(start) and L_(RBs), and the terminal apparatus 1 acquiresRB_(start) and L_(RBs) from the RIV. RB_(start) indicates the startposition of the resource allocated with reference to the physicalresource block index 0 corresponding to the initial UL BWP. In otherwords, numbering of the resource allocation indicated by the RAR ULgrant starts from the physical resource block index 0 (the lowest numberof the physical resource block of the UL BWP to which the resourceassignment is applied) corresponding to the initial UL BWP.

According to an aspect of the present embodiment, in thenon-contention-based random access procedure, the terminal apparatus 1may always determine the active UL BWP as the UL BWP to which theresource assignment is applied. In other words, in thenon-contention-based random access procedure, N^(size) _(BWP) is thenumber of resource blocks indicating the bandwidth of the active UL BWP.Also, bits are truncated or inserted with respect to the Msg3 PUSCHfrequency resource assignment using the terminal apparatus 1, thedetermined N^(size) _(BWP). Bits of the resource block assignment to betruncated or of the resource block assignment to be expanded indicatesthe value of RIV. The terminal apparatus 1 fixes that the RIV is to begenerated using determined N^(size) _(BWP) as N^(size) _(BWP) in FIG.12(A). The RIV is generated from RB_(start) and L_(RBs), and theterminal apparatus 1 acquires RB_(start) and L_(RBs) from the RIV.RB_(start) indicates the start position of the allocation resource withreference to the physical resource block index 0 corresponding to theactive UL BWP. In other words, numbering of the resource allocationindicated by the RAR UL grant starts from the physical resource blockindex 0 (the lowest number of the physical resource block of the UL BWPto which the resource assignment is applied) corresponding to the activeUL BWP.

In view of the example described above, in the contention-based randomaccess procedure, the size of the initial UL BWP is used for N^(size)_(BWP) in FIG. 12(A) for a case in which the DCI format 1_0 thatschedules the PDSCH (DL-SCH transport block) including the RAR UL grantindicating resource block assignment information is detected in thecommon search space (for example, the type1-PDCCH common search space)in CORESET#0 (or the additional common CORESET configured for theinitial DL BWP). Here, the DCI format 1_0 is the DCI format 1_0 to whichthe CRC parity bit scrambled with corresponding RA-RNTI.

According to the aforementioned aspect, in the non-contention-basedrandom access procedure, the terminal apparatus 1 determines the activeUL BWP as the UL BWP to which the resource assignment is applied,regardless of whether the CORESET associated with the type1-PDCCH commonsearch space set is the common CORESET. Also, in thenon-contention-based random access procedure, the terminal apparatus 1determines the active UL BWP as the UL BWP to which the resourceassignment is applied, regardless of whether the DL BWP for whichconfiguration information of the CORESET associated with the type1-PDCCHcommon search space set has been configured is the initial DL BWP.

In other words, the terminal apparatus 1 determines either the initialUL BWP or the active UL BWP as the UL BWP (N^(size) _(BWP)) to which theresource assignment is applied, based on which of the contention-basedrandom access procedure and the non-contention-based random accessprocedure the random access procedure is. In a case that the randomaccess procedure is the contention-based random access procedure, forexample, the terminal apparatus 1 may determine the initial UL BWP asthe UL BWP to which the resource assignment is applied. Also, N^(size)_(BWP) is the number of resource blocks indicating the bandwidth of theinitial UL BWP. In a case that the random access procedure is thenon-contention-based random access procedure, the terminal apparatus 1may determine the active UL BWP as the UL BWP to which the resourceassignment is applied. N^(size) _(BWP) is the number of resource blocksindicating the bandwidth of the active UL BWP.

The bit number of N_(UL, hop) hopping bits may be provided by 1 bit or 2bits, based on whether the size (N^(size) _(BWP)) of the UL BWP to whichthe resource assignment is applied has exceeded the predetermined valueY of the number of resource blocks. In other words, N^(size) _(BWP) maybe N^(size) _(BWP) indicating the bandwidth of the UL BWP, to which theresource assignment is applied, which is determined according to theaforementioned aspect. In other words, in a case that N^(size) _(BWP) issmaller than the predetermined value Y of the number of resource blocks,N_(UL, hop) hopping bits may be provided as 1 bit. The second hopfrequency offset for PUSCH transmission of the message 3 isFloor(N^(size) _(BWP)/2) or Floor(N^(size) _(BWP)/4). In a case thatN^(size) _(BWP) is equal to or greater than the predetermined value Y ofthe number of resource blocks, N_(UL, hop) hopping bits may be providedas 2 bits. The second hop frequency offset for PUSCH transmission of themessage 3 is Floor(N^(size) _(BWP)/2), Floor(N^(size) _(BWP)/4), or−Floor(N^(size) _(BWP)/4).

As described above, resource block numbering (RB indexing) of theresource allocation (uplink type0 and/or type1 resource allocation) isdetermined in the UL BWP, which indicates the resource allocation, towhich the resource assignment is applied. Specifically, in a case that abandwidth part (BWP) indicator field has not been configured in the DCIformat, the RB numbering of the resource allocation is determined in theactive BWP of the terminal apparatus 1. However, even in a case that thebandwidth part (BWP) indicator field has not been configured in the DCIformat, the RB numbering of the resource allocation is determined in theinitial UL BWP for the DCI format 0_0 detected in an arbitrary commonsearch space set in CORESET#0 (or the additional common CORESETconfigured for the initial DL BWP). In other words, even in the case inwhich the bandwidth part (BWP) indicator field has not been configuredin the DCI format, the RB numbering of the resource allocation isdetermined in the initial UL BWP for the DCI format 0_0 detected in thearbitrary common search space set in the CORESET configured for theinitial DL BWP. Also, even in the case in which the bandwidth part (BWP)indicator field has not been configured in the DCI format, the RBnumbering of the resource allocation is determined in the active BWP forthe DCI format 0_0 detected in an arbitrary common search space set inthe CORESET configured for the active BWP.

In a case that the bandwidth part (BWP) indicator field has beenconfigured in the DCI format, the RB numbering of the resourceallocation is determined in the BWP indicated in the BWP indicatorfield. However, even in the case in which the bandwidth part (BWP)indicator field has been configured in the DCI format, the RB numberingof the resource allocation is determined in the initial UL BWP for theDCI format 0_0 detected in an arbitrary common search space set inCORESET#0 (or the additional common CORESET configured for the initialDL BWP). The terminal apparatus 1 fixes the UL BWP to which the resourceassignment is applied first and then determines resource allocation inthe fixed UL BWP at the time of detection of the PDCCH for the terminalapparatus 1.

The RB numbering of the uplink type1 resource allocation may bedetermined in the active BWP of the terminal apparatus 1 for the RAR ULgrant. In the contention-based random access procedure, the RB numberingof the resource allocation indicated by the RAR UL grant is determinedin the initial UL BWP of the terminal apparatus 1. In other words, inthe contention-based random access procedure, the RB numbering of theresource allocation in the frequency direction in the PUSCH scheduled bythe RAR UL grant (MAC RAR) is determined in the initial UL BWP of theterminal apparatus 1. Also, in the non-contention-based random accessprocedure, the RB numbering of the resource allocation indicated by theRAR UL grant is determined in the active UL BWP of the terminalapparatus 1. In other words, in the non-contention-based random accessprocedure, the RB numbering of the resource allocation in the frequencydirection in the PUSCH scheduled by the RAR UL GRANT (MAC RAR) isdetermined in the active UL BWP of the terminal apparatus 1.

Also, in the contention-based random access procedure, the RB numberingof the resource allocation indicated by the RAR UL grant may bedetermined in the initial UL BWP of the terminal apparatus 1 in a casethat the DCI format 1_0 that schedules the PDSCH (DL-SCH transportblock) including the RAR UL grant is detected in the common search space(for example, the type1-PDCCH common search space) in CORESET#0. Here,the DCI format 1_0 is the DCI format 1_0 to which the CRC parity bitscrambled with corresponding RA-RNTI. Also, in the contention-basedrandom access procedure, the RB numbering of the resource allocationindicated by the RAR UL grant may be determined in the active UL BWP ofthe terminal apparatus 1 in a case that the DCI format 1_0 thatschedules the PDSCH (DL-SCH transport block) including the RAR UL grantis detected in the common search space (for example, the type1-PDCCHcommon search space) in the additional common CORESET (or the CORESETother than CORESET#0). However, the RB numbering of the resourceallocation indicated by the RAR UL grant may be determined in theinitial UL BWP of the terminal apparatus 1 in a case that the DCI format1_0 that schedules the PDSCH (DL-SCH transport block) including the RARUL grant is detected in the common search space (for example, thetype1-PDCCH common search space) in the additional common CORESETconfigured for the initial DL BWP.

Also, the RB numbering of the resource allocation is determined by theUL BWP to which the RAR UL grant (the resource block assignment includedin the RAR UL grant) is applied for the DCI format 0_0 that schedulesretransmission of the Msg3 PUSCH. The DCI format 0_0 that schedules theretransmission of the Msg3 PUSCH is scrambled with TC-RNTI. The DCIformat 0_0 does not include the BWP indicator field.

Message 3 (S803)

The terminal apparatus 1 performs PUSCH transmission of the message 3based on the RAR UL grant included in the RAR message received in S802.In the PUSCH corresponding to the transmission of the message 3, acorresponding preamble is transmitted in the serving cell transmitted inthe PRACH. Specifically, the PUSCH corresponding to the transmission ofthe message 3 is transmitted in the active UL BWP.

Retransmission of Message 3 (S803 a)

Retransmission of the message 3 is scheduled by the DCI format 0_0 towhich the CRC parity bit scrambled with TC-RNTI included in the RARmessage is added. In other words, the PUSCH retransmission of thetransport block transmitted in the PUSCH corresponding to the RAR ULgrant included in the RAR message is scheduled by the DCI format 0_0 towhich the CRC parity bit scrambled with TC-RNTI is added. The DCI format0_0 is transmitted in the PDCCH of the type1-PDCCH common search spaceset. In other words, the terminal apparatus 1 may monitor the DCI format0_0 that schedules the retransmission of the message 3 aftertransmitting the message 3 in S803. In S803 a, in a case that theterminal apparatus 1 detects the DCI format 0_0 that schedules theretransmission of the message 3, then S803 b is executed.

A frequency domain resource assignment field is included in the DCIformat 0_0 that schedules the retransmission of the message 3. The bitsof the field are provided based on the initial UL BWP. Specifically, thenumber of bits of the field is calculated by (Expression 4)Ceiling(log₂(N^(UL, BWP) _(RB)(N^(UL, BWP) _(RB)+1)/2)). Here,N^(UL, BWP) _(RB) is the number of resource blocks indicating thebandwidth of the initial UL BWP. In other words, regardless of which ofone or a plurality of UL BWP configured for the terminal apparatus 1 theresource for retransmitting the message 3 is tried to be scheduled with,the number of bits of the frequency domain resource assignment field isa fixed value (same value) based on the bandwidth of the initial UL BWP.

In one example, N^(UL, BWP) _(RB) may be provided based on the type ofthe random access procedure. For example, N^(UL, BWP) _(RB) is thenumber of resource blocks indicating the bandwidth of the initial UL BWPin the contention-based random access procedure. For example,N^(UL, BWP) _(RB) is the number of resource blocks indicating thebandwidth of the active UL BWP in the non-contention-based random accessprocedure.

The terminal apparatus 1 needs to perform interpretation to adapt thebits of the frequency domain resource assignment field based on theinitial UL BWP to the bandwidth of the UL BWP to which the frequencydomain resource assignment (frequency domain resource assignment field)is applied. As described above, the terminal apparatus 1 determines theUL BWP to which the Msg3 PUSCH frequency resource assignment is appliedin a case that the terminal apparatus 1 truncates or inserts bits forthe Msg3 PUSCH frequency resource assignment. Here, the UL BWP to whichthe frequency domain resource assignment field included in the DCIformat 0_0 is applied may be determined by the same determination methodas that described above for the UL BWP to which the Msg3 PUSCH frequencyresource assignment is applied. In other words, the UL BWP to which thefrequency domain resource assignment included in the DCI format 0_0 isapplied may be the UL BWP to which the Msg3 PUSCH frequency resourceassignment is applied. In other words, the terminal apparatus 1 mayspecify resource block allocation in the frequency direction in thePUSCH for the UL BWP to which the Msg3 PUSCH frequency resourceassignment is applied, based on the value of the RIV indicated in thefrequency domain resource assignment field.

In a case that the UL BWP to which the Msg3 PUSCH frequency resourceassignment is applied is the initial UL BWP (or the initial active ULBWP), for example, the UL BWP to which the frequency domain resourceassignment field included in the DCI format 0_0 is applied is theinitial UL BWP. The base station apparatus 3 generates the RIV using thesize of the initial UL BWP to which the resource assignment is applied,fixes the bit sequence to be included in the field of the frequencyresource assignment, and transmits the bit sequence to the terminalapparatus 1. Then, the terminal apparatus 1 specifies the resourceallocation in the frequency direction in the PUSCH of the physicalresource block of the UL BWP (initial UL BWP) to which the resourceassignment is applied, regardless of which of the UL BWPs the actuallyactivated UL BWP is. The terminal apparatus 1 can specify RB_(start) andL_(RBs) corresponding to the physical resource block of the initial BWPusing FIG. 12(A). Here, N^(size) _(BWP) in FIG. 12(A) is a resourceblock indicating the bandwidth of the initial UL BWP. In other words,the value of the RIV indicated in the frequency domain resourceassignment field is provided based on the size of the initial UL BWP towhich the resource assignment is applied and RB_(start) and L_(RBs)corresponding to the resource block of the initial UL BWP. RB_(start) isthe number of resource blocks indicating the start position of theresource allocation with reference to the physical resource block index0 of the initial BWP UL. L_(RBs) cannot exceed the number of resourceblocks indicating the bandwidth of the initial UL BWP. In other words,the numbering of the resources indicated in the frequency domainresource assignment field starts from the smallest number of thephysical resource block of the initial UL BWP.

In view of the example described above, the size of the initial UL BWPis used for N^(size) _(BWP) in FIG. 12(A) for a case in which the DCIformat 0_0 is detected in the type-1 PDCCH common search space set inthe CORESET#0 or the additional common CORESET configured for theinitial DL BWP. Here, the DCI format 0_0 may be monitored by the CSS. Inother words, the terminal apparatus 1 specifies resource blockallocation in the frequency direction of the initial UL BWP even in acase that the activated UL BWP (the UL BWP with which uplink data istransmitted) is not the initial UL BWP. The value of the resource blockoffset between the physical resource block index 0 of the initial UL BWPand the physical resource block index 0 of the active UL BWP is providedby a higher layer parameter locationAndBandwidth configured for eachBWP. Also, the size of the initial UL BWP is used for N^(size) _(BWP) inFIG. 12(A) for a case in which the DCI format 0_0 is detected in anarbitrary common search space set in CORESET#0 or the additional commonCORESET configured for the initial DL BWP.

In a case that the UL BWP to which the Msg3 PUSCH frequency resourceassignment is applied is the active UL BWP, for example, the UL BWP towhich the frequency domain resource assignment field included in the DCIformat 0_0 is applied is the active UL BWP. The base station apparatus 3generates the RIV using the size of the active UL BWP to which theresource assignment is applied, fixes the bit sequence to be included inthe field of the frequency resource assignment, and transmits the bitsequence to the terminal apparatus 1. Then, the terminal apparatus 1specifies resource allocation in the frequency direction in the PUSCH ofthe active UL BWP to which the frequency domain resource assignment isapplied. In a case that the active UL BWP is not the initial active ULBWP, the terminal apparatus 1 can specify RB_(start) and L_(RBs)corresponding to the physical resource block of the active UL BWP byusing the method of FIG. 12(B). In this case, N^(nitial) _(BWP) in FIG.12(B) is the number of resource blocks indicating the bandwidth of theinitial UL BWP. N^(active) _(BWP) is the number of resource blocksindicating the bandwidth of the active UL BWP. The value of the RIV isprovided based on the number N^(nitial) _(BWP) of resource blocksindicating the bandwidth of the initial BWP, the start positionRB′_(start) of the resource blocks, and the number of L′_(RBs) of theresource blocks continuously allocated. RB_(start) is the number ofresource blocks indicating the start position of the resource allocationwith reference to the physical resource block index 0 of the active ULBWP. In other words, numbering of the resources indicated in thefrequency domain resource assignment field is started from the lowestnumber of the physical resource block of the active UL BWP.

In the view of the example described above, the method in FIG. 12(B) maybe applied to the case in which although the size of the DCI format 0_0in the CSS (the arbitrary common search space set or the type-1 PDCCHcommon search space set) (or the size of the frequency domain resourceassignment field included in the DCI format) is derived from the size ofthe initial UL BWP, the UL BWP to which the resource assignment of theMsg3 PUSCH frequency resource assignment field is applied is the activeUL BWP. In other words, the method in FIG. 12(B) may be applied to thecase in which although the size of the DCI format 0_0 in the CSS (or thesize of the frequency domain resource assignment field included in theDCI format) is derived from the size of the initial UL BWP, the size ofthe DCI format 0_0 (or the size of the frequency domain resourceassignment field included in the DCI format) is applied to anotheractive UL BWP (the activated UL BWP other than the initial UL BWP).Here, the CSS is a CSS associated with the CORESET other than CORESET#0and the additional common CORESET configured for the initial DL BWP. Inother words, the CSS is a CSS associated with the CORESET configured forthe DL BWP other than the initial DL BWP. Here, the DCI format 0_0 maybe scrambled with TC-RNTI. In other words, the method in FIG. 12(B) maybe applied to the case in which although the DCI format is derived fromthe size of the initial UL BWP, the UL BWP to which the DCI format isapplied is another active UL BWP, and the search space set in the DCIformat is the common search space set associated with the CORESETconfigured for the BWP other than the initial DL BWP or the UE-specificsearch space set.

As described above, the number of bits in the frequency domain resourceassignment field included in the DCI format 0_0 is provided byN^(UL, BWP) _(RB) indicating the bandwidth of the initial UL BWP. Thenumber of bits of N_(UL, hop) hopping bits included in the frequencydomain resource assignment field may be provided by 1 bit or 2 bitsbased on whether or not N^(UL, BWP) _(RB) has exceeded the predeterminedvalue Y of the number of resource blocks. The number of bits ofN_(UL, hop) hopping bits included in the frequency domain resourceassignment field may be provided by 1 bit or 2 bits based on whether ornot N^(size) _(BWP) has exceeded the predetermined value Y of the numberof resource blocks. Here, N^(size) _(BWP) is the number of resourceblocks indicating the bandwidth of the UL BWP to which the frequencydomain resource assignment field is applied. In other words, in a casethat N^(size) _(BWP) is smaller than the predetermined value Y of thenumber of resource blocks, N_(UL, hop) hopping bits may be provided as 1bit. The second hop frequency offset for the PUSCH transmission of themessage 3 is Floor(N^(size) _(BWP)/2) or Floor(N^(size) _(BWP)/4). In acase that N^(size) _(BWP) is equal to or greater than the predeterminedvalue Y of the number of resource blocks, N_(UL, hop) hopping bits maybe provided as 2 bits. The second hop frequency offset for the PUSCHtransmission of the message 3 is Floor(N^(size) _(BWP)/2),Floor(N^(size) _(BWP)/4), or −Floor(N^(size) _(BWP)/4).

Retransmission of Message 3 (S803 b)

In S803 a, in a case that the DCI format 0_0 to which the CRC parity bitscrambled with TC-RNTI is added is detected, then the terminal apparatus1 performs PUSCH retransmission of the transport block transmitted inS803.

Message 4 (S804)

In order to respond to the PUSCH transmission of the message 3, theterminal apparatus 1 for which the C-RNTI is not indicated monitors theDCI format 1_0 scheduling the PDSCH including UE collision resolutionidentity (UE contention resolution identity). Here, a CRC parity bitscrambled with corresponding TC-RNTI is added to the DCI format 1_0. Inorder to respond to the PDSCH reception with UE collision resolutionidentity, the terminal apparatus 1 transmits HARQ-ACK information in thePUCCH. The PUCCH transmission may be performed by an active UL BWP towhich the message 3 is transmitted.

In this manner, the terminal apparatus 1 that performs the random accessprocedure can perform uplink data transmission to the base stationapparatus 3.

Hereinafter, configurations of apparatuses according to the presentembodiment will be described.

FIG. 15 is an overview block diagram illustrating a configuration of theterminal apparatus 1 according to the present embodiment. Asillustrated, the terminal apparatus 1 is configured to include a radiotransmission and/or reception unit 10 and a higher layer processing unit14. The radio transmission and/or reception unit 10 is configured toinclude an antenna unit 11, a radio frequency (RF) unit 12, and abaseband unit 13. The higher layer processing unit 14 is configured toinclude a medium access control layer processing unit 15 and a radioresource control layer processing unit 16. The radio transmission and/orreception unit 10 will also be referred to as a transmission unit, areception unit, a monitoring unit, or a physical layer processing unit.The higher layer processing unit 14 will also be referred to as ameasurement unit, a selection unit, or a control unit 14.

The higher layer processing unit 14 outputs uplink data (which may alsobe referred to as a transport block) generated through a user operationor the like to the radio transmission and/or reception unit 10. Thehigher layer processing unit 14 performs processing for some or all ofthe Medium Access Control (MAC) layer, the Packet Data ConvergenceProtocol (PDCP) layer, the Radio Link Control (RLC) layer, and the RadioResource Control (RRC) layer. The higher layer processing unit 14 mayhave a function of selecting one reference signal from one or aplurality of reference signals based on measurement values of thereference signals. The higher layer processing unit 14 may have thefunction of selecting a PRACH occasion associated with the selected onereference signals from one or a plurality of PRACH occasions. The higherlayer processing unit 14 may have a function of specifying one indexfrom one or a plurality of indexes configured in a higher layer (forexample, an RRC layer) and sets the specified index as a preamble indexin a case that bit information included in information received by theradio transmission and/or reception unit 10 and indicating an initiationof the random access procedure is a predetermined value. The higherlayer processing unit 14 may have a function of specifying an indexassociated with the selected reference signal and setting the specifiedindex to the preamble index among one or a plurality of indexesconfigured in the RRC. The higher layer processing unit 14 may have afunction of determining a next available PRACH occasion based on thereceived information (for example, SSB index information and/or maskindex information). The higher layer processing unit 14 may have afunction of selecting an SS/PBCH block based on the received information(for example, SSB index information).

The medium access control layer processing unit 15 included in thehigher layer processing unit 14 performs processing for the mediumaccess control layer (MAC layer). The medium access control layerprocessing unit 15 controls transmission of a scheduling request basedon various types of configuration information/parameters managed by theradio resource control layer processing unit 16.

The radio resource control layer processing unit 16 included in thehigher layer processing unit 14 performs processing for the radioresource control layer (RRC layer). The radio resource control layerprocessing unit 16 manages various types of configurationinformation/parameters of the terminal apparatus 1 itself. The radioresource control layer processing unit 16 sets various types ofconfiguration information/parameters based on a higher layer signalreceived from the base station apparatus 3. In other words, the radioresource control layer processing unit 16 sets the various types ofconfiguration information/parameters based on information indicatingvarious types of configuration information/parameters received from thebase station apparatus 3. The radio resource control layer processingunit 16 controls (specifies) resource allocation based on downlinkcontrol information received from the base station apparatus 3.

The radio transmission and/or reception unit 10 performs processing,such as modulation, demodulation, coding, and decoding, for the physicallayer. The radio transmission and/or reception unit 10 separates,demodulates, and decodes a signal received from the base stationapparatus 3 and outputs the decoded information to the higher layerprocessing unit 14. The radio transmission and/or reception unit 10generates a transmission signal by modulating and coding data andtransmits the transmission signal to the base station apparatus 3. Theradio transmission and/or reception unit 10 may have a function ofreceiving one or a plurality of reference signals in a certain cell. Theradio transmission and/or reception unit 10 may have a function ofreceiving information specifying one or a plurality of PRACH occasions(for example, SSB index information and/or mask index information). Theradio transmission and/or reception unit 10 may have a function ofreceiving a signal including indication information indicating aninitiation of a random access procedure. The radio transmission and/orreception unit 10 may have a function of receiving information forreceiving information specifying a predetermined index. The radiotransmission and/or reception unit 10 may have a function of receivinginformation specifying an index of the random access preamble. The radiotransmission and/or reception unit 10 may have a function oftransmitting the random access preamble on the PRACH occasion determinedby the higher layer processing unit 14.

The RF unit 12 converts (down-converts) a signal received via theantenna unit 11 into a baseband signal through orthogonal demodulationand removes unnecessary frequency components. The RF unit 12 outputs aprocessed analog signal to the baseband unit.

The baseband unit 13 converts the analog signal input from the RF unit12 into a digital signal. The baseband unit 13 removes a portioncorresponding to a Cyclic Prefix (CP) from the converted digital signal,performs a Fast Fourier Transform (FFT) on the signal from which the CPhas been removed, and extracts a signal in the frequency domain.

The baseband unit 13 generates an OFDM symbol by performing Inverse FastFourier Transform (IFFT) on data, adds CP to the generated OFDM symbol,generates a baseband digital signal, and converts the baseband digitalsignal into an analog signal. The baseband unit 13 outputs the convertedanalog signal to the RF unit 12.

The RF unit 12 removes unnecessary frequency components from the analogsignal input from the baseband unit 13 using a low-pass filter,up-converts the analog signal into a signal with a carrier frequency,and transmits the up-converted signal via the antenna unit 11. Also, theRF unit 12 amplifies a power. In addition, the RF unit 12 may include afunction to determine a transmission power of an uplink signal and/or anuplink channel transmitted in a serving cell. The RF unit 12 will alsobe referred to as a transmit power control unit.

FIG. 16 is an overview block diagram illustrating a configuration of thebase station apparatus 3 according to the present embodiment. Asillustrated, the base station apparatus 3 is configured to include aradio transmission and/or reception unit 30 and a higher layerprocessing unit 34. The radio transmission and/or reception unit 30 isconfigured to include an antenna unit 31, an RF unit 32, and a basebandunit 33. The higher layer processing unit 34 is configured to include amedium access control layer processing unit 35 and a radio resourcecontrol layer processing unit 36. The radio transmission and/orreception unit 30 will also be referred to as a transmission unit, areception unit, a monitoring unit, or a physical layer processing unit.A control unit configured to control operations of each component basedon various conditions may separately be provided. The higher layerprocessing unit 34 will also be referred to as a control unit 34.

The higher layer processing unit 34 performs processing for some or allof the Medium Access Control (MAC) layer, the Packet Data ConvergenceProtocol (PDCP) layer, the Radio Link Control (RLC) layer, and the RadioResource Control (RRC) layer. The higher layer processing unit 34 mayhave a function of specifying one reference signal from one or aplurality of reference signals based on random access preamble receivedby the radio transmission and/or reception unit 30. The higher layerprocessing unit 34 may specify a PRACH occasion of monitoring the randomaccess preamble at least from SSB index information and mask indexinformation.

The medium access control layer processing unit 35 included in thehigher layer processing unit 34 performs processing for the MAC layer.The medium access control layer processing unit 35 performs processingassociated with a scheduling request based on various types ofconfiguration information/parameters managed by the radio resourcecontrol layer processing unit 36.

The radio resource control layer processing unit 36 included in thehigher layer processing unit 34 performs processing for the RRC layer.The radio resource control layer processing unit 36 generates downlinkcontrol information (an uplink grant and a downlink grant) includingresource allocation information in the terminal apparatus 1. The radioresource control layer processing unit 36 generates or acquires, from ahigher node, downlink control information, downlink data (a transportblock and a random access response) allocated in a physical downlinkshared channel, system information, an RRC message, MAC Control Element(CE), and the like and outputs them to the radio transmission and/orreception unit 30. Also, the radio resource control layer processingunit 36 manages various types of configuration information/parametersfor each terminal apparatus 1. The radio resource control layerprocessing unit 36 may set various types of configurationinformation/parameters for each terminal apparatus 1 via a higher layersignal. In other words, the radio resource control layer processing unit36 transmits/broadcasts information indicating the various types ofconfiguration information/parameters. The radio resource control layerprocessing unit 36 may transmit/broadcast information for specifyingconfiguration of one or a plurality of reference signals in a certaincell.

In a case that an RRC message, a MAC CE, and/or a PDCCH is transmittedfrom the base station apparatus 3 to the terminal apparatus 1, and theterminal apparatus 1 performs processing based on the reception, thebase station apparatus 3 performs processing (control of the terminalapparatus 1 and the system) on the assumption that the terminalapparatus is performing the processing. In other words, the base stationapparatus 3 sends the terminal apparatus 1 such an RRC message, a MACCE, and/or a PDCCH that causes the terminal apparatus to performprocessing based on the reception thereof.

The radio transmission and/or reception unit 30 has a function oftransmitting one or a plurality of reference signals. The radiotransmission and/or reception unit 30 may have a function of receiving asignal including a beam failure recovery request transmitted from theterminal apparatus 1. The radio transmission and/or reception unit 30may have a function of transmitting information specifying one or aplurality of PRACH occasions (for example, SSB index information and/ormask index information) to the terminal apparatus 1. The radiotransmission and/or reception unit 30 may have a function oftransmitting information specifying a predetermined index. The radiotransmission and/or reception unit 30 may have a function oftransmitting information specifying an index of the random accesspreamble. The radio transmission and/or reception unit 30 may have afunction of monitoring the random access preamble in the PRACH occasionidentified by the higher layer processing unit 34. Since some of otherfunctions of the radio transmission and/or reception unit 30 are similarto those of the radio transmission and/or reception unit 10, descriptionwill be omitted. Note that in a case that the base station apparatus 3is connected to one or a plurality of transmission reception points 4,some or all of the functions of the radio transmission and/or receptionunit 30 may be included in each of the transmission reception points 4.

Also, the higher layer processing unit 34 transmits (transfers) orreceives control messages or user data between the base stationapparatuses 3 or between a higher network apparatus (MME, Serving-GW(S-GW)) and the base station apparatus 3. Although the other componentsof the base station apparatus 3 and transmission path of data (controlinformation) among the components are omitted in FIG. 16, it is obviousthat the base station apparatus 3 has a plurality of blocks that haveother functions needed to operate as the base station apparatus 3 ascomponents. For example, a radio resource management layer processingunit and an application layer processing unit are present in the higherlayer processing unit 34. Also, the higher layer processing unit 34 mayhave a function of configuring a plurality of scheduling requestresources that correspond to the plurality of reference signalstransmitted form the radio transmission and/or reception unit 30,respectively.

Note that “units” in the drawings are elements that realize thefunctions and each procedure of the terminal apparatus 1 and the basestation apparatus 3, which are also expressed with terms such assections, circuits, configuring apparatuses, devices, units, and thelike.

Each of the units with the reference signs 10 to 16 applied theretoincluded in the terminal apparatus 1 may be configured as a circuit.Each of the units with the reference signs 30 to 36 applied theretoincluded in the base station apparatus 3 may be configured as a circuit.

(1) More specifically, a terminal apparatus 1 according to a firstaspect of the present invention includes: a receiving unit 10 configuredto receive a PDSCH including an RAR message; and a control unit 16configured to control resource allocation based on a first fieldindicating Msg3 PUSCH frequency resource assignment indicated by a firstUL grant included in the RAR message, wherein the control unit truncatesX bits from a least significant bit to bits of the first field in a casethat the number of first resource blocks is smaller than or equal to avalue of a predetermined number of resource blocks or inserts Y mostsignificant bits that are set to a value ‘0” after a hopping bit in thebits of the first field in a case that the number of first resourceblocks is greater than the value of the predetermined number of resourceblocks, and the number of the first resource blocks is provided based ona type of a random access procedure.

(2) In the first aspect of the present invention, the number of firstresource blocks is a number of resource blocks that indicate an activeUL BWP bandwidth in a case that the type of the random access procedureis a non-contention-based random access procedure.

(3) In the first aspect of the present invention, the number of firstresource blocks is a number of resource blocks that indicate an initialUL BWP bandwidth in a case that the type of the random access procedureis a contention-based random access procedure.

(4) A base station apparatus 3 according to a second aspect of thepresent invention includes: a control unit 36 configured to generate afirst UL grant including a first field indicating Msg3 PUSCH frequencyresource assignment indicating resource allocation; and a transmissionunit 30 configured to transmit a PDSCH including an RAR messageincluding the first UL grant, wherein the control unit truncates X bitsfrom a least significant bit to bits of the first field in a case thatthe number of first resource blocks is smaller than or equal to a valueof a predetermined number of resource blocks and inserts Y mostsignificant bits that are set to a value ‘0’ after a hopping bit in thebits of the first field in a case that the number of first resourceblocks is greater than the value of the predetermined number of resourceblocks, and the number of first resource blocks is provided based on atype of a random access procedure.

(5) In the second aspect of the present invention, the number of firstresource blocks is a number of resource blocks that indicate an activeUL BWP bandwidth in a case that the type of the random access procedureis a non-contention-based random access procedure.

(6) In the second aspect of the present invention, the number of firstresource blocks is a number of resource blocks that indicate an initialUL BWP bandwidth in a case that the type of the random access procedureis a contention-based random access procedure.

(7) A terminal apparatus 1 that performs a contention-based randomaccess procedure according to a third aspect of the present inventionincludes: a reception unit 10 configured to receive a PDSCH including anRAR message; and a control unit 16 configured to control resourceallocation based on a first field indicating Msg3 PUSCH frequencyresource assignment indicated by a first UL grant included in the RARmessage, wherein the control unit truncates X bits from a leastsignificant bit to bits of the first field in a case that the number offirst resource blocks is smaller than or equal to a value of apredetermined number of resource blocks and inserts Y most significantbits that are set to a value ‘0’ after a hopping bit in bits of thefirst field in a case that the number of first resource blocks isgreater than the value of the predetermined number of resource blocks,the number of first resource blocks is a number of resource blocksindicating a UL BWP bandwidth that has the same BWP identifier as a DLBWP for which CORESET configuration information indicated by atype1-PDCCH common search space set is configured, the type1-PDCCHcommon search space set is a search space set used for a random accessprocedure, and the CORESET is time and frequency resources for searchingfor downlink control information.

(8) A base station apparatus 3 that communicates with a terminalapparatus 1 that performs a contention-based random access procedureaccording to a fourth aspect of the present invention includes: acontrol unit 36 configured to generate a first UL grant including afirst field indicating Msg3 PUSCH frequency resource assignmentindicating resource allocation; and a transmission unit 30 configured totransmit a PDSCH including an RAR message, wherein the first UL grant isincluded in the RAR message, the control unit truncates X bits from aleast significant bit to bits of the first field in a case that thenumber of first resource blocks is smaller than or equal to a value of apredetermined number of resource blocks and inserts Y most significantbits that are set to a value ‘0’ after a hopping bit in the bits of thefirst field in a case that the number of first resource blocks isgreater than the value of the predetermined number of resource blocks,the number of first resource blocks is the number of resource blocksindicating a UL BWP bandwidth having the same BWP identifier as a DL BWPfor which CORESET configuration information indicated by a type1-PDCCHcommon search space set is configured, the type1-PDCCH common searchspace set is a search space set used for a random access procedure, andthe CORESET is time and frequency resources for searching for downlinkcontrol information.

(9) A terminal apparatus 1 according to a fifth aspect of the presentinvention includes: a reception unit 10 configured to receive a firstDCI format scrambled with TC-RNTI in a search space set; and a controlunit 16 configured to specify resource allocation of a PUSCH based on asecond field indicating frequency domain resource assignment included inthe first DCI format, wherein bits of a first field indicating Msg3PUSCH frequency resource assignment indicated by a first UL grantincluded in an RAR message are truncated from a least significant bitand/or a most significant bit is inserted thereinto, based on the numberof first resource blocks indicating a first UL BWP bandwidth, the sizeof the second field is derived from an initial UL BWP bandwidth, and thecontrol unit specifies resource block allocation in a frequencydirection to be applied to the first UL BWP based on a value of RIVindicated by the second field.

(10) In the fifth aspect of the present invention, in a case that thefirst UL BWP is an active UL BWP other than an initial UL BWP, and thesearch space set is a common search space associated with CORESETconfigured for a BWP other than an initial DL BWP or a UE-specificsearch space, the control unit identifies a first start position ofresource allocation and the number of continuously allocated firstresource blocks based on the initial UL BWP from the value of the RIVindicated by the second field, applies to the physical resource blocksof the active UL BWP a second start position and the number of secondresource blocks obtained by scaling the first start position and thenumber of first resource blocks with a coefficient K, and specifiesresource allocation of a PUSCH, and the CORESET is time and frequencyresources for searching for downlink control information.

(11) In the fifth aspect of the present invention, in a case that thefirst UL BWP is an active UL BWP other than an initial UL BWP, and thesearch space set is a common search space associated with CORESETconfigured for an initial DL BWP, the control unit identifies a firststart position of resource allocation and the number of continuouslyallocated first resource blocks based on the initial UL BWP from thevalue of the RIV indicated by the second field, applies the identifiedfirst start position and the number of first resource blocks to aphysical resource block of the initial UL BWP, and specifies resourceallocation of a PUSCH.

(12) In a fifth aspect of the present invention, in a case that thefirst UL BWP is an initial UL BWP, a first start position of resourceallocation and the number of continuously allocated first resourceblocks are identified based on the initial UL BWP from the value of theRIV indicated by the second field, the identified first start positionand the number of first resource blocks are applied to a physicalresource block of the initial UL BWP, and resource allocation of a PUSCHis specified.

(13) In a fifth aspect of the present invention, the coefficient K isprovided by a value rounded down to a closest exponent of 2 at a ratiobetween a bandwidth of the active UL BWP and the initial UL BWP in acase that the bandwidth of the active UL BWP is greater than thebandwidth of the initial UL BWP and is provided by 1 otherwise.

(14) A base station apparatus 3 according to a sixth aspect of thepresent invention includes: a control unit 36 configured to generate afirst DCI format including a second field indicating frequency domainresource assignment indicating resource allocation information; and atransmission unit 30 configured to transmit the first DCI format in atype1-PDCCH common search space set, wherein the first DCI format isscrambled with TC-RNTI, bits in a case that a first field indicatingMsg3 PUSCH frequency resource assignment indicated by a first UL grantincluded in an RAR message are truncated from a least significant bit,and/or a most significant bit is inserted thereinto, based on the numberof first resource blocks indicating the bandwidth of the first UL BWP,the size of the second field is derived from a bandwidth of an initialUL BWP, and the control unit specifies resource block allocation in afrequency direction of a PUSCH of the first UL BWP to be applied to theterminal apparatus and generates a value of RIV indicated by the secondfield.

(15) In the sixth aspect of the present invention, in a case that thefirst UL BWP is an active UL BWP other than an initial UL BWP, andCORESET associated with the common search space set is CORESETconfigured for a BWP other than an initial DL BWP, the control unitidentifies a first start position of resource allocation and the numberof continuously allocated first resource blocks based on the initial ULBWP from the generated value of the RIV indicated by the second field,applies a second start position and the number of second resource blocksobtained by scaling the first start position and the number of firstresource blocks with a coefficient K to a physical resource block of theactive UL BWP, and specifies resource allocation of a PUSCH to beapplied to the terminal apparatus, and the CORESET is time and frequencyresources for searching for downlink control information.

(16) In the sixth aspect of the present invention, in a case that thefirst UL BWP is an active UL BWP other than an initial UL BWP, andCORESET associated with the common search space set is CORESETconfigured for an initial DL BWP, the control unit identifies a firststart position of resource allocation and the number of continuouslyallocated first resource blocks based on the initial UL BWP from thegenerated value of the RIV indicated by the second field, applies theidentified first start position and the number of first resource blocksto a physical resource block of the initial UL BWP, and specifiesresource allocation of a PUSCH to be applied to the terminal apparatus,and the CORESET is time and frequency resources for searching fordownlink control information.

(17) In the sixth aspect of the present invention, in a case that thefirst UL BWP is an initial UL BWP, the control unit identifies a firststart position of resource allocation and the number of continuouslyallocated first resource blocks based on the initial UL BWP from thegenerated value of the RIV indicated by the second field, applies theidentified first start position and the number of first resource blocksto a physical resource block of the initial UL BWP, and specifiesresource allocation of a PUSCH to be applied to the terminal apparatus.

(18) In the sixth aspect of the present invention, in a case that thebandwidth of the active UL BPW is larger than the bandwidth of theinitial UL BWP, the coefficient K is provided by a value rounded down toa closest exponent of 2 with a ratio between the bandwidth of the activeUL BWP and the initial UL BWP and is provided by 1 otherwise.

In this manner, the terminal apparatus 1 can efficiently communicatewith the base station apparatus 3.

A program running on an apparatus according to the present invention maybe a program that controls a central processing unit (CPU) or the liketo cause a computer to function to realize the functions of theembodiment according to the present invention. The program orinformation handled by the program is temporarily stored in a volatilememory such as a random access memory (RAM), a non-volatile memory suchas a flash memory, a hard disk drive (HDD), or other storage devicesystem.

Note that the program for realizing the functions in the embodimentaccording to the present invention may be recorded in a computerreadable recording medium. The functions may be realized by causing thecomputer system to read and execute the program recorded in therecording medium. The “computer system” described here is a computersystem incorporated in an apparatus and is assumed to include anoperating system and hardware such as a peripheral device. Also, the“computer readable recording medium” may be a semiconductor recordingmedium, an optical recording medium, a magnetic recording medium, amedium that dynamically retains the program for a short period of time,or other computer readable recording medium.

Also, each functional block or various features of the apparatuses usedin the aforementioned embodiment may be implemented or executed on anelectric circuit, for example, an integrated circuit or a plurality ofintegrated circuits. An electric circuit designed to execute thefunctions described in the specification may include a general-purposeprocessor, a digital signal processor (DSP), an application specificintegrated circuit (ASIC), a field programmable gate array (FPGA), orother programmable logic devices, discrete gates or transistor logics,discrete hardware components, or a combination thereof. Thegeneral-purpose processor may be a microprocessor or may be a processorof a known type, a controller, a micro-controller, or a state machine.The aforementioned electric circuit may be configured using a digitalcircuit, or may be configured using an analog circuit. Also, in a casethat a technology for an integrated circuit that can replace a currentintegrated circuit appears with advances in semiconductor technologies,one or a plurality of aspects of the present invention can use a newintegrated circuit according to the technology.

Note that although the example in which the embodiment according to thepresent invention is applied to the communication system including thebase station apparatus and the terminal apparatus has been described,the embodiment can also be applied to a system in which terminalsperform communication therebetween, such as Device to Device (D2D).

Note that the invention of the present application is not limited to theaforementioned embodiments. Although an example of the apparatuses hasbeen described in the embodiments, the invention of the presentapplication is not limited thereto and can be applied to a terminalapparatus or a communication apparatus for a stationary type or anon-movable type electronic device placed indoors or outdoors, forexample, an AV apparatus, a kitchen apparatus, a cleaning or washingapparatus, an air conditioning apparatus, an office apparatus, automaticvending machine, or other household apparatuses.

Although the embodiments of the present invention have been described indetail with reference to drawings, specific configurations are notlimited to the embodiments and include modifications in design and thelike without departing from the gist of the present invention. Also,various modifications can be added to the present invention within thescope indicated by the claims, and embodiments that can be obtained byappropriately combining technical means disclosed in differentembodiments are also included in the technical scope of the presentinvention. Moreover, configurations achieved by replacing elements thatare described in the aforementioned embodiments and exhibit similareffects are also included in the technical scope of the presentinvention.

1-6. (canceled)
 7. A terminal apparatus comprising: a reception unitconfigured to receive an MIB that configures a first control resourceset (CORESET), receive an SIB1 that configures a second CORESET, receivefirst information that configures an initial uplink bandwidth part (ULBWP) and second information that configures an additional UL BWP, andreceive a first DCI format that schedules a PUSCH in a common searchspace; and a transmission unit configured to identify a set of allocatedresource blocks based on a first field included in the first DCI formatand transmit the PUSCH in an active UL BWP, the active UL BWP being a ULBWP resulting from activation of either the initial UL BWP or theadditional UL BWP, wherein in a case that the common search space is afirst common search space, a first value indicated by the first field isprovided based on a size of the initial UL BWP, a first start position,and the number of first resource blocks continuously allocated, thefirst common search space is a common search space used for a randomaccess procedure, a CORESET associated with the first common searchspace is configured to be the first CORESET or the second CORESET, thefirst start position is a start position of the set of the allocatedresource blocks, and the number of first resource blocks is the numberof resource blocks continuously allocated in the set of allocatedresource blocks.
 8. A base station apparatus that communicates with aterminal apparatus, the base station comprising: a transmission unitconfigured to transmit an MIB that configures a first control resourceset (CORESET), transmit an SIB1 that configures a second CORESET,transmit first information that configures an initial uplink bandwidthpart (UL BWP) and second information that configures an additional ULBWP, generate a first field based on a set of resource blocks allocatedto the terminal apparatus, and transmit a first DCI format including thegenerated first field in a common search space; and a reception unitconfigured to receive a PUSCH in an active UL BWP, the active UL BWP forthe terminal apparatus being a UL BWP resulting from activation ofeither the initial UL BWP or the additional UL BWP, wherein in a casethat the common search space is a first common search space, a firstvalue indicated by the first field is provided based on a size of theinitial UL BWP, a first start position, and the number of first resourceblocks continuously allocated, the first common search space is a commonsearch space used for a random access procedure, a CORESET associatedwith the first common search space is configured to be the first CORESETor the second CORESET, the first start position is a start position ofthe set of the allocated resource blocks, and the number of firstresource blocks is the number of resource blocks continuously allocatedin the set of allocated resource blocks.
 9. A communication method for aterminal apparatus comprising: receiving an MIB that configures a firstcontrol resource set (CORESET), receiving an SIB1 that configures asecond CORESET, receiving first information that configures an initialuplink bandwidth part (UL BWP) and second information that configures anadditional UL BWP, and receiving a first DCI format that schedules aPUSCH in a common search space; and identifying a set of allocatedresource blocks based on a first field included in the first DCI formatand transmitting the PUSCH in an active UL BWP, the active UL BWP beinga UL BWP resulting from activation of either the initial UL BWP or theadditional UL BWP, wherein in a case that the common search space is afirst common search space, a first value indicated by the first field isprovided based on a size of the initial UL BWP, a first start position,and the number of first resource blocks continuously allocated, thefirst common search space is a common search space used for a randomaccess procedure, a CORESET associated with the first common searchspace is configured to be the first CORESET or the second CORESET, thefirst start position is a start position of the set of the allocatedresource blocks, and the number of first resource blocks is the numberof resource blocks continuously allocated in the set of allocatedresource blocks.
 10. A communication method for a base station apparatusthat communicates with a terminal apparatus, the method comprising:transmitting an MIB that configures a first control resource set(CORESET), transmitting an SIB1 that configures a second CORESET,transmitting first information that configures an initial uplinkbandwidth part (UL BWP) and second information that configures anadditional UL BWP, generating a first field based on a set of resourceblocks allocated to the terminal apparatus, and transmitting a first DCIformat including the generated first field in a common search space; andreceiving a PUSCH in an active UL BWP, the active UL BWP for theterminal apparatus being a UL BWP resulting from activation of eitherthe initial UL BWP or the additional UL BWP, wherein in a case that thecommon search space is a first common search space, a first valueindicated by the first field is provided based on a size of the initialUL BWP, a first start position, and the number of first resource blockscontinuously allocated, the first common search space is a common searchspace used for a random access procedure, a CORESET associated with thefirst common search space is configured to be the first CORESET or thesecond CORESET, the first start position is a start position of the setof the allocated resource blocks, and the number of first resourceblocks is the number of resource blocks continuously allocated in theset of allocated resource blocks.
 11. An integrated circuit that ismounted in a terminal apparatus and causes the terminal apparatus toperform: receiving an MIB that configures a first control resource set(CORESET), receiving a SIB1 that configures a second CORESET, receivingfirst information that configures an initial uplink bandwidth part (ULBWP) and second information that configures an additional UL BWP, andreceiving a first DCI format that schedules a PUSCH in a common searchspace; and identifying a set of allocated resource blocks based on afirst field included in the first DCI format and transmitting the PUSCHin an active UL BWP, the active UL BWP being a UL BWP resulting fromactivation of either the initial UL BWP or the additional UL BWP,wherein in a case that the common search space is a first common searchspace, a first value indicated by the first field is provided based on asize of the initial UL BWP, a first start position, and the number offirst resource blocks continuously allocated, the first common searchspace is a common search space used for a random access procedure, aCORESET associated with the first common search space is configured tobe the first CORESET or the second CORESET, the first start position isa start position of the set of the allocated resource blocks, and thenumber of first resource blocks is the number of resource blockscontinuously allocated in the set of allocated resource blocks.
 12. Anintegrated circuit that is mounted in a base station apparatus thatcommunicates with a terminal apparatus, the integrated circuit causingthe base station apparatus to perform: transmitting an MIB thatconfigures a first control resource set (CORESET), transmitting an SIB1that configures a second CORESET, transmitting first information thatconfigures an initial uplink bandwidth part (UL BWP) and secondinformation that configures an additional UL BWP, generating a firstfield based on a set of resource blocks allocated to the terminalapparatus, and transmitting a first DCI format including the generatedfirst field in a common search space; and receiving a PUSCH in an activeUL BWP, the active UL BWP for the terminal apparatus being a UL BWPresulting from activation of either the initial UL BWP or the additionalUL BWP, wherein in a case that the common search space is a first commonsearch space, a first value indicated by the first field is providedbased on a size of the initial UL BWP, a first start position, and thenumber of first resource blocks continuously allocated, the first commonsearch space is a common search space used for a random accessprocedure, a CORESET associated with the first common search space isconfigured to be the first CORESET or the second CORESET, the firststart position is a start position of the set of the allocated resourceblocks, and the number of first resource blocks is the number ofresource blocks continuously allocated in the set of allocated resourceblocks.